a(n) = ( binomial(7*n,2*n)*binomial(7*n/2,2*n)*binomial(2*n,n)^2 ) / binomial(7*n/2,n)^2.
A352652
a(n) = ( binomial(7*n,2*n)*binomial(7*n/2,2*n)*binomial(2*n,n)^2 ) / binomial(7*n/2,n)^2.
Terms
- a(0) =1a(1) =30a(2) =2860a(3) =343200a(4) =45643500a(5) =6435891280a(6) =942422020540
External references
- oeis: A352652