92935

Appears in sequences

• a(n) is the number of permutations w of 1,2,...,n such that both w and w^{-1} are alternating.at n=13A007999
• a(n) is the number of permutations w of 1,2,...,n such that w is alternating and w^{-1} is reverse alternating.at n=13A332344
• Square array read by upward antidiagonals: T(n, k) is the number of n-ary strings of length k containing 00.at n=52A340156
• The number of quaternary strings of length n containing 00.at n=9A351529