a(n) = binomial(3*n,3*n/2)*binomial(2*n,n)*binomial(5*n/2,n/2)/binomial(n,n/2).

A275652

a(n) = binomial(3*n,3*n/2)*binomial(2*n,n)*binomial(5*n/2,n/2)/binomial(n,n/2).

Terms

    a(0) =1a(1) =10a(2) =300a(3) =11440a(4) =485100a(5) =21841260a(6) =1022041020a(7) =49128552000

External references