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 A036828 #19 Jul 08 2025 21:57:47
%S A036828 0,1,17,125,637,2637,9549,31501,97037,283661,795661,2158605,5697549,
%T A036828 14696461,37175309,92471309,226689037,548667405,1313079309,3111125005,
%U A036828 7305429005,17016291341,39346765837,90378862605,206342979597,468486979597,1058239676429
%N A036828 A036827/2.
%C A036828 This sequence is related to A036826 by a(n) = n*A036826(n) - Sum_{i=0..n-1} A036826(i). - _Bruno Berselli_, Mar 06 2012
%H A036828 Bruno Berselli, <a href="/A036828/b036828.txt">Table of n, a(n) for n = 0..1000</a>
%H A036828 <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (9,-32,56,-48,16).
%F A036828 G.f.: -x*(4*x^2+8*x+1)/((x-1)*(2*x-1)^4). - Maksym Voznyy (voznyy(AT)mail.ru), Aug 13 2009
%F A036828 a(n) = 2^n*(n^3-3*n^2+9*n-13)+13. - _Bruno Berselli_, Mar 06 2012
%t A036828 LinearRecurrence[{9, -32, 56, -48, 16}, {0, 1, 17, 125, 637}, 27] (* _Bruno Berselli_, Mar 06 2012 *)
%o A036828 (Magma) m:=26; R<x>:=PowerSeriesRing(Integers(), m); [0] cat Coefficients(R!(-(4*x^2+8*x+1)/((x-1)*(2*x-1)^4))); // _Bruno Berselli_, Mar 06 2012
%o A036828 (PARI) a(n) = 2^n*(n^3-3*n^2+9*n-13)+13 \\ _Bruno Berselli_, Mar 06 2012
%Y A036828 Cf. A036826, A209359.
%K A036828 nonn,easy
%O A036828 0,3
%A A036828 _N. J. A. Sloane_
%E A036828 Typo in definition corrected by _R. J. Mathar_, Sep 16 2009