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%I #11 Apr 28 2020 06:37:53
%S 0,0,4,12,24,28,80,128,112,200,236,356,472,652,656,940,1040,1300,1600,
%T 1948,2048,2588,2856,3260,3716,4492,4572,5324,5904,6508,7200,8144,
%U 8664,10296,10548,11664,12580,13860,14596,15980,17312,18516,19692,22152,22912
%N Number of pentagons in the graph formed by drawing the lines connecting any two of the 2*(n+2) perimeter points of a 3 X (n+1) rectangular grid of points (or equally, a 2 X n grid of squares).
%C See A331452 (the illustrations for T(n,2)) for pictures of these graphs.
%H Lars Blomberg, <a href="/A332608/b332608.txt">Table of n, a(n) for n = 1..100</a>
%H Scott R. Shannon, <a href="/A331452/a331452_1.txt">Data specifically for nX2 (or 2Xn) rectangles</a>
%Y Cf. A331452, A331453, A331454, A331763, A331765, A331766, A332599, A332600, A331457, A332606, A332607, A332609.
%K nonn
%O 1,3
%A _Scott R. Shannon_ and _N. J. A. Sloane_, Mar 12 2020
%E a(21) and beyond from _Lars Blomberg_, Apr 28 2020