300 (number) nontotient. 315 = 3 × 5 × 7. 315 is a Harshad number 316 = 2 × 79. 316 is a centered triangular number and a centered heptagonal number 317 is a prime number, Eisenstein prime with no imaginary part, Chen prime, and a strictly non-palindromic number. 317 is also shorthand for the LM317 adjustable regulator chip. It is also the area code for the Indianapolis region. 318 = 2 × 3 × 53. It is a sphenic number, nontotient, and the sum of twelve consecutive primes (7 + 11 + 13 + 17 + 19 + 23 + 29
Prime number problem. The problem asked for the value of the infinite sum formula_71 which today can be recognized as the value formula_72 of the Riemann zeta function. This function is closely connected to the prime numbers and to one of the most significant unsolved problems in mathematics, the Riemann hypothesis. Euler showed that formula_73. The reciprocal of this number, formula_74, is the limiting probability that two random numbers selected uniformly from a large range are relatively prime (have no factors in common). The distribution of primes in the large, such as the question how many primes are smaller than a given,