a(0) = 1, a(n) = 5*binomial(6*(n-1),n-1), for n > 0.

A380607

a(0) = 1, a(n) = 5*binomial(6*(n-1),n-1), for n > 0.

Terms

    a(0) =1a(1) =5a(2) =30a(3) =330a(4) =4080a(5) =53130a(6) =712530a(7) =9738960a(8) =134891640a(9) =1886744970a(10) =26589681300a(11) =376970137830

External references