A055862 Fourth column of triangle A055858.

0, 0, 0, 36, 400, 5400, 86436, 1605632, 34012224, 810000000, 21435888100, 624333422592, 19851622826256, 684376513673216, 25430282226562500, 1013309916158361600, 43104723599206637824, 1949779138161985486848

Offset

0,4

Links

Table of n, a(n) for n=0..17.

Formula

a(i)=0, i=0, 1, 2; a(n)= (n^2)*(n+1)^(n-2), n >= 3.

E.g.f.: -x*(1+4*x)/2 + (W(-x)^2)*(1-W(-x))/((1+W(-x))*x*2), W(x) principal branch of Lambert's function.

Crossrefs

a(n)=A055858(n, 3). Cf. A000312, A000169, A055860, A055861.

Sequence in context: A164583 A273229 A264361 * A105095 A027782 A179099

Adjacent sequences: A055859 A055860 A055861 * A055863 A055864 A055865

Keyword

nonn,easy

Author

Wolfdieter Lang Jun 20 2000

Status

approved