574560

Appears in sequences

• Triangle read by rows: T(n,k) is the number of permutations p of [n] such that the length of the longest 2-stack sortable initial segment of p is equal to k.at n=48A094785
• Magic products of 5 X 5 multiplicative magic squares.at n=20A111031
• Triangle where T(n,k) = n!*[x^k] ( x/(2*x + log(1-x)) )^(n+1), for n>=k>=0, read by rows.at n=38A118787
• The 2n-th derivative of exp(1 - 1/(1 - x^2)) evaluated at 0.at n=5A131815
• Number of nX5 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 0 and 1 0 1 vertically.at n=6A208025
• Number of 7 X n 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 0 and 1 0 1 vertically.at n=4A208032
• Denominators of the partial sums of the reciprocals of the Dedekind psi function (A001615).at n=41A357819
• Denominators of the partial alternating sums of the reciprocals of the Dedekind psi function (A001615).at n=41A357821
• For n > 1, if n appears in the sequence, a(n) = a(n-1) - n if nonnegative and not already in the sequence, otherwise a(n) = a(n-1) + n. Otherwise a(n+1) = a(n)/(n+1) if (n+1)|a(n), otherwise a(n)*(n+1), a(1) = 1 and a(2) = 1*2.at n=9A362698
• a(n) = n! / (floor(n/3))! - n! / (floor(n/2))!.at n=10A374648