21571984

Appears in sequences

• Number of permutations of 4 indistinguishable copies of 1..n with exactly 6 adjacent element pairs in decreasing order.at n=3A151644
• Irregular triangle read by rows: T(n,k) = Sum_{i=0..k} (-1)^i * binomial(4*n+1,i) * binomial(k+4-i,4)^n, 0 <= k <= 4*(n-1).at n=21A236463
• Triangle in which the g.f. for row n is (1-x)^(4*n+1) * Sum_{j>=0} binomial(n+j-1,j)^4 * x^j, read by rows of k=0..3*n terms.at n=28A262014