a(n) = ((2*n+1)!!)^3 * (Sum_{k=1..n} 1/(2*k+1)^3).

A335091

a(n) = ((2*n+1)!!)^3 * (Sum_{k=1..n} 1/(2*k+1)^3).

Terms

    a(0) =0a(1) =1a(2) =152a(3) =55511a(4) =41625144a(5) =56246975289

External references