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import Mathlib
import Mathlib.Analysis.SpecialFunctions.Pow.Real


set_option linter.unusedVariables.analyzeTactics true

open Real Set

lemma mylemma_1
  (x a: β„• β†’ ℝ)
  (hxp: βˆ€ (i : β„•), 0 < x i)
  (hβ‚€: βˆ€ (n : β„•),
    1 ≀ n ∧ n ≀ 2023 β†’
      a n = sqrt ((Finset.sum (Finset.Ico 1 (n + 1)) fun k => x k)
      * Finset.sum (Finset.Ico 1 (n + 1)) fun k => 1 / x k)) :
  βˆ€ (n : β„•), (1 ≀ n ∧ n ≀ 2022) β†’ a (n) < a (n + 1) := by
  intros n hn
  have hβ‚‚: a n = sqrt ((Finset.sum (Finset.Ico 1 (n + 1)) fun k => x k)
              * Finset.sum (Finset.Ico 1 (n + 1)) fun k => 1 / x k) := by
    refine hβ‚€ n ?_
    constructor
    . exact hn.1
    linarith
  have h₃: a (n + 1) = sqrt ((Finset.sum (Finset.Ico 1 (n + 2)) fun k => x k)
              * Finset.sum (Finset.Ico 1 (n + 2)) fun k => 1 / x k) := by
    refine hβ‚€ (n + 1) ?_
    constructor
    . linarith
    linarith
  rw [hβ‚‚,h₃]
  refine sqrt_lt_sqrt ?_ ?_
  . refine le_of_lt ?_
    refine mul_pos ?_ ?_
    . refine Finset.sum_pos ?_ ?_
      . exact fun i _ => hxp i
      . simp
        linarith
    . refine Finset.sum_pos ?_ ?_
      intros i _
      exact one_div_pos.mpr (hxp i)
      . simp
        linarith
  have gβ‚€: 1 ≀ n + 1 := by linarith
  rw [Finset.sum_Ico_succ_top gβ‚€ _, Finset.sum_Ico_succ_top gβ‚€ _]
  repeat rw [add_mul, mul_add]
  have hβ‚„: 0 < (Finset.sum (Finset.Ico 1 (n + 1)) fun k => x k) * (1 / x (n + 1)) +
    x (n + 1) * ((Finset.sum (Finset.Ico 1 (n + 1)) fun k => 1 / x k) + 1 / x (n + 1)) := by
      refine add_pos ?_ ?_
      . refine mul_pos ?_ ?_
        . refine Finset.sum_pos ?_ ?_
          . exact fun i _ => hxp i
          . simp
            linarith
        . exact one_div_pos.mpr (hxp (n + 1))
      . refine mul_pos ?_ ?_
        . exact hxp (n + 1)
        . refine add_pos ?_ ?_
          . refine Finset.sum_pos ?_ ?_
            . intros i _
              exact one_div_pos.mpr (hxp i)
            . simp
              linarith
          exact one_div_pos.mpr (hxp (n + 1))
  linarith


lemma mylemma_amgm
  (b1 b2 b3 b4 :ℝ)
  (hb1: 0 ≀ b1)
  (hb2: 0 ≀ b2)
  (hb3: 0 ≀ b3)
  (hb4: 0 ≀ b4) :
  (4 * (b1 * b2 * b3 * b4) ^ (4:ℝ)⁻¹ ≀ b1 + b2 + b3 + b4) := by
  let w1 : ℝ := (4:ℝ)⁻¹
  let w2 : ℝ := w1
  let w3 : ℝ := w2
  let w4 : ℝ := w3
  rw [mul_comm]
  refine mul_le_of_le_divβ‚€ ?_ (by norm_num) ?_
  . refine add_nonneg ?_ hb4
    refine add_nonneg ?_ hb3
    exact add_nonneg hb1 hb2
  have hβ‚€: (b1^w1 * b2^w2 * b3^w3 * b4^w4) ≀ w1 * b1 + w2 * b2 + w3 * b3 + w4 * b4 := by
    refine geom_mean_le_arith_mean4_weighted (by norm_num) ?_ ?_ ?_ hb1 hb2 hb3 hb4 ?_
    . norm_num
    . norm_num
    . norm_num
    . norm_num
  repeat rw [mul_rpow _]
  ring_nf at *
  linarith
  repeat { assumption }
  . exact mul_nonneg hb1 hb2
  . exact hb4
  . refine mul_nonneg ?_ hb3
    exact mul_nonneg hb1 hb2



lemma mylemma_2
  (x a: β„• β†’ ℝ)
  (hxp: βˆ€ (i : β„•), 0 < x i)
  (hβ‚€: βˆ€ (n : β„•),
    1 ≀ n ∧ n ≀ 2023 β†’
      a n = sqrt ((Finset.sum (Finset.Ico 1 (n + 1)) fun k => x k)
            * (Finset.sum (Finset.Ico 1 (n + 1)) fun k => 1 / x k)))
  (n: β„•)
  (hn: 1 ≀ n ∧ n ≀ 2021) :
  (4 * a n ≀
    (Finset.sum (Finset.Ico 1 (n + 1)) fun k => x k) * (1 / x (n + 1) + 1 / x (n + 2)) +
      (x (n + 1) + x (n + 2)) * Finset.sum (Finset.Ico 1 (n + 1)) fun k => 1 / x k) := by
      repeat rw [mul_add, add_mul]
      have g₁₁: 0 ≀ Finset.sum (Finset.Ico 1 (1 + n)) fun x_1 => x x_1 := by
        refine le_of_lt ?_
        refine Finset.sum_pos ?_ ?_
        . exact fun i _ => hxp i
        . simp
          linarith
      have g₁₂: 0 ≀ Finset.sum (Finset.Ico 1 (1 + n)) fun x_1 => (x x_1)⁻¹ := by
        refine le_of_lt ?_
        refine Finset.sum_pos ?_ ?_
        . intros i _
          exact inv_pos.mpr (hxp i)
        . simp
          linarith
      have h₃₂: 4 * ( ((Finset.sum (Finset.Ico 1 (n + 1)) fun k => x k) * (1 / x (n + 1))) *
          ((Finset.sum (Finset.Ico 1 (n + 1)) fun k => x k) * (1 / x (n + 2))) *
          ((x (n + 1) * Finset.sum (Finset.Ico 1 (n + 1)) fun k => 1 / x k)) *
          (x (n + 2) * Finset.sum (Finset.Ico 1 (n + 1)) fun k => 1 / x k) ) ^ (4:ℝ)⁻¹
        ≀ (Finset.sum (Finset.Ico 1 (n + 1)) fun k => x k) * (1 / x (n + 1)) +
          (Finset.sum (Finset.Ico 1 (n + 1)) fun k => x k) * (1 / x (n + 2)) +
          ((x (n + 1) * Finset.sum (Finset.Ico 1 (n + 1)) fun k => 1 / x k) +
          x (n + 2) * Finset.sum (Finset.Ico 1 (n + 1)) fun k => 1 / x k) := by
            let b1:ℝ := (Finset.sum (Finset.Ico 1 (n + 1)) fun k => x k) * (1 / x (n + 1))
            let b2:ℝ := (Finset.sum (Finset.Ico 1 (n + 1)) fun k => x k) * (1 / x (n + 2))
            let b3:ℝ := (x (n + 1) * Finset.sum (Finset.Ico 1 (n + 1)) fun k => 1 / x k)
            let b4:ℝ := x (n + 2) * (Finset.sum (Finset.Ico 1 (n + 1)) fun k => 1 / x k)
            have hb1: b1 = (Finset.sum (Finset.Ico 1 (n + 1)) fun k => x k) * (1 / x (n + 1)) := by
              exact rfl
            have hb2: b2 = (Finset.sum (Finset.Ico 1 (n + 1)) fun k => x k) * (1 / x (n + 2)) := by
              exact rfl
            have hb3: b3 = (x (n + 1) * Finset.sum (Finset.Ico 1 (n + 1)) fun k => 1 / x k) := by
              exact rfl
            have hb4: b4 = x (n + 2) * (Finset.sum (Finset.Ico 1 (n + 1)) fun k => 1 / x k) := by
              exact rfl
            rw [← hb1, ← hb2, ← hb3, ← hb4]
            have gβ‚€: 4 * (b1 * b2 * b3 * b4) ^ (4:ℝ)⁻¹ ≀ b1 + b2 + b3 + b4 := by
              have b1p: 0 ≀ b1 := by
                rw [hb1]
                refine mul_nonneg ?_ ?_
                . ring_nf
                  exact g₁₁
                . refine le_of_lt ?_
                  exact one_div_pos.mpr (hxp (n + 1))
              have b2p: 0 ≀ b2 := by
                rw [hb2]
                refine mul_nonneg ?_ ?_
                . ring_nf
                  exact g₁₁
                . refine le_of_lt ?_
                  exact one_div_pos.mpr (hxp (n + 2))
              have b3p: 0 ≀ b3 := by
                rw [hb3]
                refine mul_nonneg ?_ ?_
                . exact LT.lt.le (hxp (n + 1))
                . ring_nf
                  exact g₁₂
              have b4p: 0 ≀ b4 := by
                rw [hb4]
                refine mul_nonneg ?_ ?_
                . exact LT.lt.le (hxp (n + 2))
                . ring_nf
                  exact g₁₂
              exact mylemma_amgm b1 b2 b3 b4 b1p b2p b3p b4p
            linarith
      have h₃₃: 4 * a (n) = 4 * (((Finset.sum (Finset.Ico 1 (n + 1)) fun k => x k) * (1 / x (n + 1))) *
          ((Finset.sum (Finset.Ico 1 (n + 1)) fun k => x k) * (1 / x (n + 2))) *
          ((x (n + 1) * Finset.sum (Finset.Ico 1 (n + 1)) fun k => 1 / x k)) *
          (x (n + 2) * Finset.sum (Finset.Ico 1 (n + 1)) fun k => 1 / x k) ) ^ (4:ℝ)⁻¹ := by
        simp
        ring_nf
        have gβ‚€: (Finset.sum (Finset.Ico 1 (1 + n)) fun x_1 => x x_1) ^ 2
            * x (1 + n) * (x (1 + n))⁻¹ * x (2 + n) * (x (2 + n))⁻¹ *
            (Finset.sum (Finset.Ico 1 (1 + n)) fun x_1 => (x x_1)⁻¹) ^ 2
          = x (1 + n) * (x (1 + n))⁻¹ * x (2 + n) * (x (2 + n))⁻¹ *
            (Finset.sum (Finset.Ico 1 (1 + n)) fun x_1 => x x_1) ^ 2 *
            (Finset.sum (Finset.Ico 1 (1 + n)) fun x_1 => (x x_1)⁻¹) ^ 2 := by
            linarith
        have g₁: x (1 + n) * (x (1 + n))⁻¹ * x (2 + n) * (x (2 + n))⁻¹ = 1 := by
          rw [mul_assoc]
          have gg₁: x (1 + n) * (x (1 + n))⁻¹ = 1 := by
            refine div_self ?_
            exact ne_of_gt (hxp (1 + n))
          have ggβ‚‚: x (2 + n) * (x (2 + n))⁻¹ = 1 := by
            refine div_self ?_
            exact ne_of_gt (hxp (2 + n))
          rw [gg₁, ggβ‚‚]
          norm_num
        rw [g₁] at gβ‚€
        rw [gβ‚€]
        simp
        repeat rw [mul_rpow]
        have gβ‚‚: ((Finset.sum (Finset.Ico 1 (1 + n)) fun x_1 => x x_1) ^ (2:ℝ)) ^ (4:ℝ)⁻¹
            = (Finset.sum (Finset.Ico 1 (1 + n)) fun x_1 => x x_1) ^ (1/(2:ℝ)) := by
              rw [← rpow_mul g₁₁ (2:ℝ) (4:ℝ)⁻¹]
              norm_num
        have g₃: ((Finset.sum (Finset.Ico 1 (1 + n)) fun x_1 => (x x_1)⁻¹) ^ (2:ℝ)) ^ (4:ℝ)⁻¹
            = (Finset.sum (Finset.Ico 1 (1 + n)) fun x_1 => (x x_1)⁻¹) ^ (1/(2:ℝ)) := by
              rw [← rpow_mul g₁₂ (2:ℝ) (4:ℝ)⁻¹]
              norm_num
        -- rw [gβ‚‚, ← sqrt_eq_rpow (Finset.sum (Finset.Ico 1 (1 + n)) fun x_1 => x x_1)]
        -- rw [g₃, ← sqrt_eq_rpow (Finset.sum (Finset.Ico 1 (1 + n)) fun x_1 => (x x_1)⁻¹)]
        have gβ‚„: a (n) = sqrt ((Finset.sum (Finset.Ico 1 (n + 1)) fun k => x k)
                  * Finset.sum (Finset.Ico 1 (n + 1)) fun k => 1 / x k) := by
          refine hβ‚€ n ?_
          constructor
          . exact hn.1
          . linarith
        norm_cast at *
        rw [gβ‚‚, g₃, ← mul_rpow]
        rw [← sqrt_eq_rpow]
        ring_nf at gβ‚„
        exact gβ‚„
        . exact g₁₁
        . exact g₁₂
        . exact sq_nonneg (Finset.sum (Finset.Ico 1 (1 + n)) fun x_1 => x x_1)
        . exact sq_nonneg (Finset.sum (Finset.Ico 1 (1 + n)) fun x_1 => (x x_1)⁻¹)
      exact Eq.trans_le h₃₃ h₃₂


lemma mylemma_3
  (x a: β„• β†’ ℝ)
  (hxp: βˆ€ (i : β„•), 0 < x i)
  (hx: βˆ€ (i j : β„•), i β‰  j β†’ x i β‰  x j)
  (hβ‚€: βˆ€ (n : β„•),
    1 ≀ n ∧ n ≀ 2023 β†’
      a n = sqrt ((Finset.sum (Finset.Ico 1 (n + 1)) fun k => x k)
            * (Finset.sum (Finset.Ico 1 (n + 1)) fun k => 1 / x k)))
  (h₀₁: βˆ€ (n : β„•), 1 ≀ n ∧ n ≀ 2023 β†’ 0 < a n) :
  (βˆ€ (n : β„•), 1 ≀ n ∧ n ≀ 2021 β†’ a n + 2 < a (n + 2)) := by
    intros n hn
    have gβ‚€: 0 ≀ a n + 2 := by
      refine le_of_lt ?_
      refine add_pos ?_ (by norm_num)
      refine h₀₁ n ?_
      constructor
      . exact hn.1
      . linarith
    have g₁: 0 ≀ a (n + 2) := by
      refine le_of_lt ?_
      refine h₀₁ (n + 2) ?_
      constructor
      . linarith
      . linarith
    rw [← sqrt_sq gβ‚€, ← sqrt_sq g₁]
    have gβ‚‚: 0 ≀ (a n + 2) ^ 2 := by exact sq_nonneg (a n + 2)
    -- simp
    refine Real.sqrt_lt_sqrt gβ‚‚ ?_
    have g₃: 0 ≀ ((Finset.sum (Finset.Ico 1 (n + 1)) fun k => x k)
        * (Finset.sum (Finset.Ico 1 (n + 1)) fun k => 1 / x k)) := by
      refine le_of_lt ?_
      refine mul_pos ?_ ?_
      . refine Finset.sum_pos ?_ ?_
        . exact fun i _ => hxp i
        . simp
          linarith
      . refine Finset.sum_pos ?_ ?_
        . intros i _
          exact one_div_pos.mpr (hxp i)
        . simp
          linarith
    have gnβ‚€: a (n) ^ 2 = ((Finset.sum (Finset.Ico 1 (n + 1)) fun k => x k)
        * (Finset.sum (Finset.Ico 1 (n + 1)) fun k => 1 / x k)) := by
      rw [← sq_sqrt g₃]
      have gβ‚„: 0 ≀ a n := by
        refine le_of_lt ?_
        refine h₀₁ n ?_
        constructor
        . exact hn.1
        . linarith
      refine (sq_eq_sqβ‚€ gβ‚„ ?_).mpr ?_
      . exact
        sqrt_nonneg
          ((Finset.sum (Finset.Ico 1 (n + 1)) fun k => x k) *
            Finset.sum (Finset.Ico 1 (n + 1)) fun k => 1 / x k)
      . refine hβ‚€ (n) ?_
        constructor
        . exact hn.1
        . linarith
    have gn₁: a (n + 2) = sqrt ((Finset.sum (Finset.Ico 1 (n + 2 + 1)) fun k => x k)
        * Finset.sum (Finset.Ico 1 (n + 2 + 1)) fun k => 1 / x k) := by
      refine hβ‚€ (n + 2) ?_
      constructor
      . linarith
      . linarith
    rw [add_sq, gn₁, sq_sqrt]
    . have gaβ‚€: 1 ≀ n + 2 := by linarith
      rw [Finset.sum_Ico_succ_top gaβ‚€ _, Finset.sum_Ico_succ_top gaβ‚€ _]
      have ga₁: 1 ≀ n + 1 := by linarith
      rw [Finset.sum_Ico_succ_top ga₁ _, Finset.sum_Ico_succ_top ga₁ _]
      rw [add_assoc, add_assoc, add_assoc]
      rw [add_mul, mul_add]
      rw [← gnβ‚€]
      repeat rw [add_assoc]
      refine add_lt_add_left ?_ (a (n) ^ 2)
      rw [mul_add (x (n + 1) + x (n + 2))]
      have hβ‚‚: 4 < (x (n + 1) + x (n + 2)) * (1 / x (n + 1) + 1 / x (n + 2)) := by
        repeat rw [add_mul, mul_add, mul_add]
        repeat rw [mul_div_left_comm _ 1 _, one_mul]
        repeat rw [div_self ?_]
        . have hcβ‚‚: x (n + 1) * x (n + 2) * (x (n + 1) / x (n + 2))
            = x (n + 1) * x (n + 1) := by
            rw [mul_assoc, ← mul_div_assoc, mul_div_right_comm, div_self ?_]
            simp
            exact ne_of_gt (hxp (n + 2))
          have hc₃: x (n + 1) * x (n + 2) * (x (n + 2) / x (n + 1))
            = x (n + 2) * x (n + 2) := by
            rw [mul_comm (x (n + 1)) (x (n + 2)), mul_assoc, ← mul_div_assoc, mul_div_right_comm, div_self ?_]
            simp
            exact ne_of_gt (hxp (n + 1))
          have hβ‚‚β‚€: 0 < x (n + 1) * x (n + 2) := by
            refine mul_pos ?_ ?_
            . exact hxp (n + 1)
            . exact hxp (n + 2)
          have h₂₁: 2 < x (n + 1) / x (n + 2) + x (n + 2) / x (n + 1) := by
            refine lt_of_mul_lt_mul_left ?_ (le_of_lt hβ‚‚β‚€)
            rw [mul_add, hcβ‚‚, hc₃, ← sq, ← sq]
            refine lt_of_sub_pos ?_
            have gh₂₁: x (n + 1) ^ 2 + x (n + 2) ^ 2 - x (n + 1) * x (n + 2) * 2
                      = (x (n + 1) - x (n + 2)) ^ 2 := by
              rw [sub_sq]
              linarith
            rw [gh₂₁]
            refine (sq_pos_iff).mpr ?_
            refine sub_ne_zero.mpr ?_
            exact hx (n+1) (n+2) (by linarith)
          linarith
        . exact ne_of_gt (hxp (n + 2))
        . exact ne_of_gt (hxp (n + 1))
      clear gnβ‚€ gn₁ gβ‚€ g₁ gβ‚‚ g₃ gaβ‚€ ga₁
      have h₃: 4 * a (n) ≀ (Finset.sum (Finset.Ico 1 (n + 1)) fun k => x k)
          * (1 / x (n + 1) + 1 / x (n + 2)) +
          ((x (n + 1) + x (n + 2))
          * Finset.sum (Finset.Ico 1 (n + 1)) fun k => 1 / x k) := by
          exact mylemma_2 (fun k => x k) a hxp hβ‚€ n hn
      linarith
    . refine mul_nonneg ?_ ?_
      . refine Finset.sum_nonneg ?_
        intros i _
        exact LT.lt.le (hxp i)
      . refine Finset.sum_nonneg ?_
        intros i _
        simp
        exact LT.lt.le (hxp i)


theorem imo_2023_p4
  (x : β„• β†’ ℝ)
  (a : β„• β†’ ℝ)
  (hxp: βˆ€ (i: β„•), (0 < x i) )
  (hx: βˆ€ (i j: β„•), (i β‰  j) β†’ (x i β‰  x j) )
  (hβ‚€: βˆ€ (n:β„•), (1 ≀ n ∧ n ≀ 2023) β†’
        a n = Real.sqrt ( (Finset.sum (Finset.Ico 1 (n + 1)) fun (k : β„•) => (x k))
            * (Finset.sum (Finset.Ico 1 (n + 1)) fun (k : β„•) => 1 / (x k)) ) )
  (h₁: βˆ€ (n:β„•), (1 ≀ n ∧ n ≀ 2023) β†’ βˆƒ (kz:β„€), (a n = ↑kz )) :
  (3034 ≀ a 2023) := by
  have ha1: a 1 = 1 := by
    have gβ‚€: sqrt ((Finset.sum (Finset.Ico 1 (1 + 1)) fun k => x k)
            * Finset.sum (Finset.Ico 1 (1 + 1)) fun k => 1 / x k) = 1 := by
      norm_num
      refine div_self ?_
      exact ne_of_gt (hxp 1)
    rw [← gβ‚€]
    exact hβ‚€ (1) (by norm_num)
  have h₀₁: βˆ€ (n : β„•), (1 ≀ n ∧ n ≀ 2023) β†’ 0 < a n := by
    intros n hn
    have ha: a n = sqrt ((Finset.sum (Finset.Ico 1 (n + 1)) fun k => x k)
       * Finset.sum (Finset.Ico 1 (n + 1)) fun k => 1 / x k) := by
        exact hβ‚€ (n) (hn)
    rw [ha]
    refine Real.sqrt_pos.mpr ?_
    refine mul_pos ?_ ?_
    . refine Finset.sum_pos ?_ ?_
      . intros i _
        exact hxp i
      simp
      linarith
    . refine Finset.sum_pos ?_ ?_
      . intros i _
        exact one_div_pos.mpr (hxp i)
      simp
      linarith
  have h₁₁: βˆ€ (n : β„•), (1 ≀ n ∧ n ≀ 2023) β†’ βˆƒ (kn:β„•), a n = ↑kn := by
    intros n hn
    have g₁₁: 0 < a n := by
      exact h₀₁ n hn
    let ⟨p, gp⟩ := h₁ n hn
    let q:β„• := Int.toNat p
    have g₁₂: ↑q = p := by
      refine Int.toNat_of_nonneg ?_
      rw [gp] at g₁₁
      norm_cast at g₁₁
      exact Int.le_of_lt g₁₁
    use q
    rw [gp]
    norm_cast
    exact id g₁₂.symm
  have h₂₁: βˆ€ (n:β„•), (1 ≀ n ∧ n ≀ 2021) β†’ a n + 2 < a (n+2) := by
    exact fun n a_1 => mylemma_3 (fun i => x i) a hxp hx hβ‚€ h₀₁ n a_1
  have hβ‚‚: βˆ€ (n:β„•), (1 ≀ n ∧ n ≀ 2021) β†’ a n + 3 ≀ a (n+2) := by
    intros n hn
    have gβ‚€: a n + 2 < a (n + 2) := by exact h₂₁ n hn
    have g₀₁: βˆƒ (p:β„•), a n = ↑p := by
      apply h₁₁
      constructor
      . linarith
      . linarith
    have gβ‚€β‚‚: βˆƒ (q:β„•), a (n + 2) = ↑q := by
      apply h₁₁
      constructor
      . linarith
      . linarith
    let ⟨p, _⟩ := g₀₁
    let ⟨q, _⟩ := gβ‚€β‚‚
    have g₁: p + 2 < q := by
      suffices g₁₁: ↑p + (2:ℝ) < ↑q
      . norm_cast at g₁₁
      . linarith
    have gβ‚‚: ↑p + (3:ℝ) ≀ ↑q := by norm_cast
    linarith
  have h₃: βˆ€ (n:β„•), (0 ≀ n ∧ n ≀ 1010) β†’ a 1 + 3 * (↑(n)  + 1) ≀ a (3 + 2 * n) := by
    intros n hn
    induction' n with d hd
    Β· simp
      exact hβ‚‚ (1) (by norm_num)
    Β· rw [mul_add]
      simp
      have gβ‚€: a (3 + 2 * d) + 3 ≀ a (3 + 2 * (d + 1)) := by
        refine hβ‚‚ (3 + 2 * d) ?_
        constructor
        . linarith
        . linarith
      have g₁: a 1 + 3 * (↑d + 1) + 3 ≀ a (3 + 2 * d) + 3 := by
        refine add_le_add_right ?_ (3)
        apply hd
        constructor
        . linarith
        . linarith
      refine le_trans (by linarith[g₁]) gβ‚€
  rw [ha1] at h₃
  have hβ‚„: (3034:ℝ)  = 1 + 3 * (↑1010 + 1) := by norm_num
  rw [hβ‚„]
  exact h₃ (1010) (by norm_num)