a(n) = n! * Sum_{k=0..n} (-1)^(n-k) * k^4 / k!.

Terms

a(0) =0a(1) =1a(2) =14a(3) =39a(4) =100a(5) =125a(6) =546a(7) =-1421a(8) =15464a(9) =-132615a(10) =1336150a(11) =-14683009a(12) =176216844a(13) =-2290790411a(14) =32071104170a(15) =-481066511925