"""
A sequence is an ordered collection of objects (usually numbers), which
are allowed to repeat. Sequences can be finite or infinite. Two examples
are the finite sequence (π,−2√,0,π)(π,−2,0,π) and the infinite sequence of
odd numbers (1,3,5,7,9,…)(1,3,5,7,9,…). We use the notation an to represent
the n-th term of a sequence.

A recurrence relation is a way of defining the terms of a sequence with
respect to the values of previous terms. In the case of Fibonacci's
rabbits from the introduction, any given month will contain the rabbits
that were alive the previous month, plus any new offspring. A key
observation is that the number of offspring in any month is equal to the
number of rabbits that were alive two months prior. As a result, if Fn
represents the number of rabbit pairs alive after the n-th month, then we
obtain the Fibonacci sequence having terms Fn that are defined by the
recurrence relation Fn=Fn−1+Fn−2Fn=Fn−1+Fn−2 (with F1=F2=1F1=F2=1 to
initiate the sequence). Although the sequence bears Fibonacci's name, it
was known to Indian mathematicians over two millennia ago.

When finding the n-th term of a sequence defined by a recurrence relation,
we can simply use the recurrence relation to generate terms for
progressively larger values of n. This problem introduces us to the
computational technique of dynamic programming, which successively builds
up solutions by using the answers to smaller cases.

Given: Positive integers n≤40n≤40 and k≤5k≤5.

Return: The total number of rabbit pairs that will be present after n months
 if we begin with 1 pair and in each generation, every pair of
reproduction-age rabbits produces a litter of k rabbit pairs (instead of
only 1 pair).
"""

n, k = map(int, raw_input().split())

n1, n2 = 1, 1
for _ in xrange(n - 2):
    tmp = n2
    n2 = n1
    n1 = n1 + (tmp * k)
print n1

"""
A sequence is an ordered collection of objects (usually numbers), which
are allowed to repeat. Sequences can be finite or infinite. Two examples
are the finite sequence (π,−2√,0,π)(π,−2,0,π) and the infinite sequence of
odd numbers (1,3,5,7,9,…)(1,3,5,7,9,…). We use the notation an to represent
the n-th term of a sequence.

A recurrence relation is a way of defining the terms of a sequence with
respect to the values of previous terms. In the case of Fibonacci's
rabbits from the introduction, any given month will contain the rabbits
that were alive the previous month, plus any new offspring. A key
observation is that the number of offspring in any month is equal to the
number of rabbits that were alive two months prior. As a result, if Fn
represents the number of rabbit pairs alive after the n-th month, then we
obtain the Fibonacci sequence having terms Fn that are defined by the
recurrence relation Fn=Fn−1+Fn−2Fn=Fn−1+Fn−2 (with F1=F2=1F1=F2=1 to
initiate the sequence). Although the sequence bears Fibonacci's name, it
was known to Indian mathematicians over two millennia ago.

When finding the n-th term of a sequence defined by a recurrence relation,
we can simply use the recurrence relation to generate terms for
progressively larger values of n. This problem introduces us to the
computational technique of dynamic programming, which successively builds
up solutions by using the answers to smaller cases.

Given: Positive integers n≤40n≤40 and k≤5k≤5.

Return: The total number of rabbit pairs that will be present after n months
 if we begin with 1 pair and in each generation, every pair of
reproduction-age rabbits produces a litter of k rabbit pairs (instead of
only 1 pair).
"""

n, k = map(int, raw_input().split())

n1, n2 = 1, 1
for _ in xrange(n - 2):
    tmp = n2
    n2 = n1
    n1 = n1 + (tmp * k)
print n1

A sequence is an ordered collection of objects (usually numbers), which are allowed to repeat. Sequences can be finite or infinite. Two examples are the finite sequence (π,−2√,0,π)(π,−2,0,π) and the infinite sequence of odd numbers (1,3,5,7,9,…)(1,3,5,7,9,…). We use the notation an to represent the n-th term of a sequence.  A recurrence relation is a way of defining the terms of a sequence with respect to the values of previous terms. In the case of Fibonacci's rabbits from the introduction, any given month will contain the rabbits that were alive the previous month, plus any new offspring. A key observation is that the number of offspring in any month is equal to the number of rabbits that were alive two months prior. As a result, if Fn represents the number of rabbit pairs alive after the n-th month, then we obtain the Fibonacci sequence having terms Fn that are defined by the recurrence relation Fn=Fn−1+Fn−2Fn=Fn−1+Fn−2 (with F1=F2=1F1=F2=1 to initiate the sequence). Although the sequence bears Fibonacci's name, it was known to Indian mathematicians over two millennia ago.  When finding the n-th term of a sequence defined by a recurrence relation, we can simply use the recurrence relation to generate terms for progressively larger values of n. This problem introduces us to the computational technique of dynamic programming, which successively builds up solutions by using the answers to smaller cases.  Given: Positive integers n≤40n≤40 and k≤5k≤5.  Return: The total number of rabbit pairs that will be present after n months  if we begin with 1 pair and in each generation, every pair of reproduction-age rabbits produces a litter of k rabbit pairs (instead of only 1 pair).