a(n) = Sum_{k=0..n} (-1)^(n-k)*(n!/k!)^2*binomial(n,k).

A119401

a(n) = Sum_{k=0..n} (-1)^(n-k)*(n!/k!)^2*binomial(n,k).

Terms

    a(0) =1a(1) =0a(2) =-3a(3) =46a(4) =-927a(5) =25476a(6) =-922715a(7) =42240402a(8) =-2337537279a(9) =147901509928

External references