%I #5 Jun 13 2015 00:51:05
%S 0,1,9,42,152,480,1392,3808,9984,25344,62720,152064,362496,851968,
%T 1978368,4546560,10354688,23396352,52494336,117047296,259522560,
%U 572522496,1257242624,2749366272,5989466112,13002342400,28135391232
%N Binomial transform of heptagonal numbers A000566.
%C Binomial transform is A084900. 2nd binomial transform of (0,1,5,0,0,0,....).
%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (6,-12,8).
%F G.f.: x(1 + 3x)/(1 - 2x)^3; a(n)=2^(n - 2)*n(5n - 1)/2.
%K easy,nonn
%O 0,3
%A _Paul Barry_, Jun 10 2003