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

A028341

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

Terms

    a(0) =1a(1) =25a(2) =505a(3) =10045a(4) =208054a(5) =4574934a(6) =107494190a(7) =2702025590a(8) =72578259391

External references