cp's OEIS Frontend

A060022 Expansion of (1-x-x^N)/((1-x)(1-x^2)(1-x^3)...(1-x^N)) for N = 3.

%I A060022 #23 May 09 2019 09:58:41
%S A060022 1,0,1,0,0,-1,-1,-3,-3,-5,-6,-8,-9,-12,-13,-16,-18,-21,-23,-27,-29,
%T A060022 -33,-36,-40,-43,-48,-51,-56,-60,-65,-69,-75,-79,-85,-90,-96,-101,
%U A060022 -108,-113,-120,-126,-133,-139,-147,-153,-161,-168,-176,-183,-192,-199,-208,-216,-225,-233,-243,-251,-261,-270,-280
%N A060022 Expansion of (1-x-x^N)/((1-x)(1-x^2)(1-x^3)...(1-x^N)) for N = 3.
%C A060022 Difference between the number of partitions of n+2 into 2 parts and the number of partitions of n+2 into 3 parts. - _Wesley Ivan Hurt_, Apr 16 2019
%H A060022 Colin Barker, <a href="/A060022/b060022.txt">Table of n, a(n) for n = 0..1000</a>
%H A060022 P. A. MacMahon, <a href="https://doi.org/10.1112/plms/s1-17.1.139">Perpetual reciprocants</a>, Proc. London Math. Soc., 17 (1886), 139-151; Coll. Papers II, pp. 584-596.
%H A060022 <a href="/index/Par#part">Index entries for sequences related to partitions</a>
%H A060022 <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (1,1,0,-1,-1,1).
%F A060022 a(n) = A004526(n+2) - A069905(n+2). - _Wesley Ivan Hurt_, Apr 16 2019
%F A060022 From _Colin Barker_, Apr 17 2019: (Start)
%F A060022 G.f.: (1 - x - x^3) / ((1 - x)^3*(1 + x)*(1 + x + x^2)).
%F A060022 a(n) = a(n-1) + a(n-2) - a(n-4) - a(n-5) + a(n-6) for n>5.
%F A060022 (End)
%o A060022 (PARI) Vec((1 - x - x^3) / ((1 - x)^3*(1 + x)*(1 + x + x^2)) + O(x^40)) \\ _Colin Barker_, Apr 17 2019
%Y A060022 Cf. A004526, A069905.
%Y A060022 Cf. For other values of N: this sequence (N=3), A060023 (N=4), A060024 (N=5), A060025 (N=6), A060026 (N=7), A060027 (N=8), A060028 (N=9), A060029 (N=10).
%K A060022 sign,easy
%O A060022 0,8
%A A060022 _N. J. A. Sloane_, Mar 17 2001