cp's OEIS Frontend

A109537 a(0)=a(1)=a(2)=a(3)=a(4)=a(5)=1; a(n)=a(n-1)+a(n-2)-a(n-4)+a(n-6) for n>=6.

%I A109537 #5 Dec 26 2022 04:54:03
%S A109537 1,1,1,1,1,1,2,3,5,8,12,18,27,40,60,90,135,203,305,458,688,1033,1551,
%T A109537 2329,3497,5251,7885,11840,17779,26697,40088,60196,90390,135729,
%U A109537 203810,306040,459548,690055,1036183,1555927,2336372,3508284,5268021,7910433
%N A109537 a(0)=a(1)=a(2)=a(3)=a(4)=a(5)=1; a(n)=a(n-1)+a(n-2)-a(n-4)+a(n-6) for n>=6.
%F A109537 G.f.: (1-x^2-x^3)/(1-x-x^2+x^4-x^6).
%p A109537 a[0]:=1: a[1]:=1: a[2]:=1: a[3]:=1: a[4]:=1: a[5]:=1: for n from 6 to 45 do a[n]:=a[n-1]+a[n-2]-a[n-4]+a[n-6] od: seq(a[n],n=0..45);
%t A109537 F[1] = 1; F[2] = 1; F[3] = 1; F[4] = 1; F[5] = 1; F[6] = 1; F[n__] := F[n] = F[n - 1] + F[n - 2] - F[n - 4] + F[n - 6] aa = Table[F[n], {n, 1, 50}]
%K A109537 nonn,easy
%O A109537 0,7
%A A109537 _Roger L. Bagula_, Jun 19 2005