a(n) = 4^n * binomial(5*n/2,n).

A386897

a(n) = 4^n * binomial(5*n/2,n).

Terms

    a(0) =1a(1) =10a(2) =160a(3) =2860a(4) =53760a(5) =1040060a(6) =20500480a(7) =409404600a(8) =8255569920a(9) =167718033340

External references