|
%I #12 Jul 27 2015 19:43:59
%S 1,9,44,207,991,4752,22769,109089,522676,2504295,11998799,57489696,
%T 275449681,1319758713,6323343884,30296960703,145161459631,
%U 695510337456,3332390227649,15966440800785,76499813776276,366532628080599
%N INVERT transform of the cubes A000578.
%C Analog of A033453 (INVERT squares) and A001906 (INVERT first powers).
%C For n>1, a(n-1) is the number of generalized compositions of n when there are i^3 different types of i, (i=1,2,...). [_Milan Janjic_, Sep 24 2010]
%H Vincenzo Librandi, <a href="/A144109/b144109.txt">Table of n, a(n) for n = 0..1000</a>
%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (5, -2, 5, -1).
%F G.f.: (1+4*x+x^2)/((1+x^2)*(1-5*x+x^2)).
%F a(n) = (9*A004254(n+1)-4*A056594(n))/5.
%t CoefficientList[Series[(1 + 4*x + x^2)/((1 + x^2)*(1 -5 *x + x^2)), {x, 0, 40}], x] (* _Vincenzo Librandi_, Dec 14 2012 *)
%Y Cf. A004254, A056594.
%K nonn,easy
%O 0,2
%A _R. J. Mathar_, Sep 11 2008
|
