7875000

Appears in sequences

• a(n) = (5*n+10)(!^5)/10(!^5), related to A052562 ((5*n)(!^5) quintic, or 5-factorials).at n=5A051691
• Triangle with T(n,k)=n!*(k-1)^k/k! where 1<=k<=n.at n=41A076482
• a(1) = 1, a(2) = (1+2)*(2+3), a(3) = (1+2+3)*(2+3+4)*(3+4+5), ... etc. Or a(n) = (T(n))*(T(n)+n)*(T(n)+2n)*(T(n)+3n)*... n terms. where T(n) = n(n+1)/2 given by A000217.at n=4A092958
• The fifth power of the unsigned Lah triangular matrix A105278.at n=23A308282