a(n) = floor(n^(n - 1) / 2) for n > 0 and otherwise 0.

A369026

a(n) = floor(n^(n - 1) / 2) for n > 0 and otherwise 0.

Terms

    a(0) =0a(1) =0a(2) =1a(3) =4a(4) =32a(5) =312a(6) =3888a(7) =58824a(8) =1048576a(9) =21523360a(10) =500000000a(11) =12968712300a(12) =371504185344

External references