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 A067154 #23 Jun 09 2025 21:17:46 %S A067154 1,0,0,0,0,0,0,0,15,0,17,18,57,0,21,44,115,0,150,104,81,112,116,0,155, %T A067154 224,429,306,560,180,555,836,663,640,1025,378,1419,660,1710,1564,1786, %U A067154 1200,2352,1050,2754,2236,2597,2700,3410,2240,3078,3190,4602,1860,5551,4898,6363,5056,8515,4950 %N A067154 Number of heptagonal regions in regular n-gon with all diagonals drawn. %D A067154 B. Poonen and M. Rubinstein, Number of Intersection Points Made by the Diagonals of a Regular Polygon, SIAM J. Discrete Mathematics, Vol. 11, pp. 135-156. %H A067154 Scott R. Shannon, <a href="/A067154/b067154.txt">Table of n, a(n) for n = 7..765</a> %H A067154 Sascha Kurz, <a href="http://www.mathe2.uni-bayreuth.de/sascha/oeis/drawing/drawing.html">m-gons in regular n-gons</a> %H A067154 B. Poonen and M. Rubinstein, <a href="http://math.mit.edu/~poonen/">The number of intersection points made by the diagonals of a regular polygon</a>, SIAM J. on Discrete Mathematics, Vol. 11, No. 1, 135-156 (1998). %H A067154 <a href="/index/Pol#Poonen">Sequences formed by drawing all diagonals in regular polygon</a> %e A067154 a(7)=1 because the center-region is a heptagon. %Y A067154 Cf. A007678, A067166, A064869, A067151, A067152, A067153, A067155, A067156, A067157, A067158, A067159. %K A067154 nonn %O A067154 7,9 %A A067154 _Sascha Kurz_, Jan 06 2002 %E A067154 a(62) and beyond from _Scott R. Shannon_, Dec 04 2021 %E A067154 Definition clarified by _N. J. A. Sloane_, Jun 09 2025