3014550

Appears in sequences

• Triangle T(n,k) = number of permutations of n elements with k 2-cycles.at n=38A114320
• The number of permutations of [n] with 2 cycles of length 2.at n=8A178669
• a(n) = n*(n+1)*(n+2)*(n+3)*(2*n+1)/12.at n=27A356251