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

A368789

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

Terms

    a(0) =0a(1) =1a(2) =19a(3) =913a(4) =91301a(5) =16434181a(6) =4831649215

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