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 A270576 #15 Mar 25 2025 20:41:15 %S A270576 1,8,48,288,1728,10368,62208,373248,2239488,13436928,80621568, %T A270576 483729408,2902376448,17414258688,104485552128,626913312768, %U A270576 3761479876608,22568879259648,135413275557888,812479653347328,4874877920083968,29249267520503808,175495605123022848,1052973630738137088 %N A270576 Expansion of g.f. (1+2*x)/(1-6*x). %C A270576 Partial sums are 1, 9, 57, 345, 2073, 12441, ... %C A270576 Essentially the same as A084477. - _R. J. Mathar_, Mar 21 2016 %H A270576 Colin Barker, <a href="/A270576/b270576.txt">Table of n, a(n) for n = 0..1000</a> %H A270576 <a href="/index/Rec#order_01">Index entries for linear recurrences with constant coefficients</a>, signature (6). %F A270576 G.f.: (1+2*x)/(1-6*x). %F A270576 a(n) = 6*a(n-1) for n>1. %F A270576 a(n) = 8*6^(n-1) for n>0. %F A270576 E.g.f.: (4*exp(6*x) - 1)/3. - _Elmo R. Oliveira_, Mar 25 2025 %o A270576 (PARI) Vec((1+2*x)/(1-6*x) + O(x^30)) %Y A270576 Cf. A000400 (powers of 6), A003949: (1+x)/(1-6*x), A084477. %K A270576 nonn,easy %O A270576 0,2 %A A270576 _Colin Barker_, Mar 19 2016