%I #9 Mar 11 2018 13:19:06

%S 0,5,10,24,35,80,90,170,220,420,364,644,780,1120,1139,1854,1748,2580,

%T 2898,3916,3450,6072,5350,7046,7398,10024,10063,14250,13795,16608,

%U 16566,21114,21595,26316,26640,32718,32370,39520,38622,52416,47558,56232,57240

%N Number of 4-cycles in the n-polygon diagonal intersection graph.

%H Andrew Howroyd, <a href="/A300552/b300552.txt">Table of n, a(n) for n = 3..100</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/GraphCycle.html">Graph Cycle</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PolygonDiagonalIntersectionGraph.html">Polygon Diagonal Intersection Graph</a>

%Y Cf. A062361 (3-cycles), A300553 (5-cycles), A300554 (6-cycles).

%K nonn

%O 3,2

%A _Eric W. Weisstein_, Mar 08 2018

%E Terms a(21) and beyond from _Andrew Howroyd_, Mar 11 2018