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 A377885 #7 Nov 12 2024 12:17:47 %S A377885 1,1,1,4,28,136,544,2080,8128,32512,130816,524800,2099200,8390656, %T A377885 33550336,134201344,536854528,2147516416,8590065664,34359869440, %U A377885 137438691328,549754765312,2199022206976,8796095119360,35184380477440,140737496743936,562949936644096 %N A377885 Cogrowth sequence of the 16-element quasihedral group SD16 = <S,T | S^8, T^2, STS^5T>. %C A377885 Gives the even terms, all the odd terms are 0. %C A377885 Also called QD16, Q8:C2. Gap identifier 16,8. %H A377885 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (6, -12, 16). %F A377885 G.f.: (6*x^3-7*x^2+5*x-1) / ((4*x-1) * (4*x^2-2*x+1)). %Y A377885 Cf. A047849 (D4), A007582 (D8), A071930 (Q8), A377840 (C8 X C2), A377883 (M4(2)). %K A377885 nonn,easy %O A377885 0,4 %A A377885 _Sean A. Irvine_, Nov 10 2024