This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A029000 #54 Jun 11 2025 03:58:34
%S A029000 1,1,2,3,4,5,8,9,12,15,18,21,27,30,36,42,48,54,64,70,80,90,100,110,
%T A029000 125,135,150,165,180,195,216,231,252,273,294,315,343,364,392,420,448,
%U A029000 476,512,540,576,612,648,684,729,765,810,855,900,945,1000,1045,1100
%N A029000 Expansion of 1/((1-x)*(1-x^2)*(1-x^3)*(1-x^6)).
%C A029000 Number of partitions of n into parts 1, 2, 3, and 6. - _Joerg Arndt_, Jul 04 2013
%H A029000 <a href="/index/Rec#order_12">Index entries for linear recurrences with constant coefficients</a>, signature (1,1,0,-1,-1,2,-1,-1,0,1,1,-1).
%F A029000 a(n) = floor((1/18)*(-3*floor((n + 2)/3) + 3*floor(n/3) + 2)*(floor(n/3) + 1) + (1/432)*(n + 6)*(2*n^2 + 24*n + 47+9*(-1)^n) + 7/36). - _Tani Akinari_, Jul 04 2013
%F A029000 a(n) = 1 + floor((2*n^3 + 36*n^2 + 183*n + 24*n*[(n mod 3)=0] + 9*n*(-1)^n)/432) where [] is Iverson bracket. - _Hoang Xuan Thanh_, Jun 10 2025
%t A029000 CoefficientList[Series[1/((1 - x) (1 - x^2) (1 - x^3) (1 - x^6)), {x, 0, 80}], x] (* _Vincenzo Librandi_, May 12 2015 *)
%o A029000 (PARI) Vec(1/((1-x)*(1-x^2)*(1-x^3)*(1-x^6))+O(x^99)) \\ _Charles R Greathouse IV_, Sep 27 2012
%o A029000 (Magma) [Floor(1/18*(-3*Floor((n + 2)/3) + 3*Floor(n/3) + 2)*(Floor(n/3) + 1) + 1/432*(n + 6)*(2*n^2 + 24*n + 47+9*(-1)^n) + 7/36): n in [0..80]]; // _Vincenzo Librandi_, May 12 2015
%K A029000 nonn,easy
%O A029000 0,3
%A A029000 _N. J. A. Sloane_
%E A029000 More terms from _Vincenzo Librandi_, May 12 2015