87336

Appears in sequences

• Triangle T(n,k) read by rows, defined by T(n,k) = (n-k)*T(n-1,k)+Sum(k=1..n, T(n-1,k)); T(1,1) = 1, T(1,k)= 0 if k >1.at n=33A089225
• Number A(n,k) of up-down sequences with k copies each of 1,2,...,n; square array A(n,k), n>=0, k>=0, read by antidiagonals.at n=41A275784
• Number of up-down sequences with 3 copies each of 1,2,...,n.at n=5A276636
• Number of up-down sequences with n copies each of 1,2,...,5.at n=3A276637
• Number of n X 2 0..1 arrays with the number of 1's horizontally or vertically adjacent to some 0 equal to the number of 0's adjacent to some 1, with top left element zero.at n=9A284159