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 A029041 #27 Jun 10 2025 08:42:01 %S A029041 1,1,1,2,2,3,4,4,5,7,8,9,11,12,14,17,18,20,24,26,29,33,35,39,44,47,51, %T A029041 57,61,66,73,77,83,91,96,103,112,118,126,136,143,152,163,171,181,194, %U A029041 203,214,228,238,251,266,277,291,308,321,336,354,368,385,405 %N A029041 Expansion of 1/((1-x)*(1-x^3)*(1-x^5)*(1-x^9)). %C A029041 Number of partitions of n into parts 1, 3, 5, and 9. - _Alois P. Heinz_, Oct 01 2014 %H A029041 <a href="/index/Rec#order_18">Index entries for linear recurrences with constant coefficients</a>, signature (1,0,1,-1,1,-1,0,-1,2,-1,0,-1,1,-1,1,0,1,-1). %F A029041 a(n) = floor((n^3+27*n^2+204*n+700+10*[3*n+29,4,0][(n mod 3)+1])/810). - _Tani Akinari_, Oct 01 2014 %F A029041 a(n) = 1 + floor((n^3+27*n^2+204*n+30*n*[(n mod 3)=0])/810) where [] is Iverson bracket. - _Hoang Xuan Thanh_, Jun 09 2025 %t A029041 CoefficientList[Series[1/((1-x)(1-x^3)(1-x^5)(1-x^9)), {x, 0, 90}], x] (* _Jinyuan Wang_, Mar 24 2020 *) %o A029041 (PARI) a(n)=round((n+9)*(n^2+18*n+52)/810+(n\3+1)*(3*!(n%3)-1)/27+[12,-5,-10][n%3+1]/81) \\ _Tani Akinari_, May 23 2014 %o A029041 (PARI) a(n)=(n^3+27*n^2+204*n+700+10*[3*n+29,4,0][n%3+1])\810 \\ _Tani Akinari_, Oct 01 2014 %o A029041 (PARI) Vec(1/((1-x)*(1-x^3)*(1-x^5)*(1-x^9)) + O(x^80)) \\ _Michel Marcus_, Oct 01 2014 %K A029041 nonn,easy %O A029041 0,4 %A A029041 _N. J. A. Sloane_