Coefficient of x^4 in expansion of (x+2) * (x+5) * ... * (x+3*n-1).

A383222

Coefficient of x^4 in expansion of (x+2) * (x+5) * ... * (x+3*n-1).

Terms

    a(0) =0a(1) =0a(2) =0a(3) =0a(4) =1a(5) =40a(6) =1275a(7) =39655a(8) =1276009a(9) =43382934a(10) =1570298610a(11) =60630265740

External references