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 A386292 #11 Jul 23 2025 00:11:25 %S A386292 1,5,11,23,34,52,68,94,109,131,151,181,200,226,250,284,299,321,341, %T A386292 371,390,416,440,474,489,511,531,561,580,606,630,664,679,701,721,751, %U A386292 770,796,820,854,869,891,911,941,960,986,1010,1044,1059,1081,1101,1131,1150 %N A386292 The maximum possible number of 9-cycles in an outerplanar graph on n vertices. %C A386292 Excluding the first 7 terms, the first differences are 8-periodic: 15, 22, 20, 30, 19, 26, 24, 34. %H A386292 <a href="/index/Rec#order_09">Index entries for linear recurrences with constant coefficients</a>, signature (1,0,0,0,0,0,0,1,-1). %F A386292 a(n) ~ (95/4)*n. %F A386292 G.f.: x^9*(8*x^15+8*x^14+8*x^13+8*x^12+18*x^11+14*x^10+18*x^9+14*x^8+26*x^7+16*x^6 + 18*x^5 + 11*x^4+12*x^3+6*x^2+4*x+1) / ((x+1)*(x^2+1)*(x^4+1)*(x-1)^2). - _Alois P. Heinz_, Jul 17 2025 %Y A386292 Cf. A385869, A386226. %K A386292 nonn,easy %O A386292 9,2 %A A386292 _Stephen Bartell_, Jul 17 2025