A075916 Third column of triangle A075501.

1, 36, 900, 19440, 390096, 7511616, 141134400, 2611802880, 47870735616, 871982724096, 15819463296000, 286235993272320, 5170077903015936, 93275375604350976, 1681524519443251200, 30298254922942709760

Offset

0,2

Comments

The e.g.f. given below is Sum_{m=0..2} A075513(3,m)*exp(6*(m+1)*x)/2!.

Links

Table of n, a(n) for n=0..15.

Formula

a(n) = A075501(n+3, 3) = (6^n)*S2(n+3, 3) with S2(n, m) := A008277(n, m) (Stirling2).

a(n) = (6^n - 8*12^n + 9*18^n)/2.

G.f.: 1/Product_{k=1..3} (1 - 6*k*x).

E.g.f.: (d^3/dx^3)(((exp(6*x)-1)/6)^3)/3! = (exp(6*x) - 8*exp(12*x) + 9*exp(18*x))/2!.

Crossrefs

Cf. A016175, A075917.

Sequence in context: A335220 A248108 A233003 * A062150 A011811 A167250

Adjacent sequences: A075913 A075914 A075915 * A075917 A075918 A075919

Keyword

nonn,easy

Author

Wolfdieter Lang, Oct 02 2002

Status

approved