350240

Appears in sequences

• Triangle read by rows: T(n,k) is the number of permutations of [n] having k-1 alternating descents (1<=k<=n). The index i is an alternating descent of a permutation p if either i is odd and p(i)>p(i+1), or i is even and p(i)<p(i+1).at n=47A145876
• Triangle read by rows: T(n,k) is the number of permutations of [n] having k-1 alternating descents (1<=k<=n). The index i is an alternating descent of a permutation p if either i is odd and p(i)>p(i+1), or i is even and p(i)<p(i+1).at n=52A145876
• Number of n X n arrays of squares of integers summing to 13.at n=2A159389
• Number of permutations of [n] having exactly two alternating descents.at n=7A302895
• Number of permutations of [n] having exactly seven alternating descents.at n=2A302900