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A340650 Irregular table read by rows: row n gives the number of 7-gon to k-gon contacts, with k>=7, for a regular n-gon with all diagonals drawn, with n>=19.

%I A340650 #17 Jan 15 2021 21:12:43
%S A340650 19,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
%T A340650 52,0,0,0,0,0,0,0,118,0,61,0,63,0,0,0,0,0,138,70,0,72,73,148,0,0,0,0,
%U A340650 158,80,0,82,83,0,0,172,0,0,178,540,0,0,93,0,93,282,95,96,194,294,0,198,99
%N A340650 Irregular table read by rows: row n gives the number of 7-gon to k-gon contacts, with k>=7, for a regular n-gon with all diagonals drawn, with n>=19.
%C A340650 For n=3 to n=18 there are no n-gons that have 7-gon to k-gon contacts, where k>=7, so the table starts at n=19.
%C A340650 See A333654 for the number of 3-gon to k-gon contacts, with k>=3.
%C A340650 See A335614 for the number of 4-gon to k-gon contacts, with k>=4.
%C A340650 See A335646 for the number of 5-gon to k-gon contacts, with k>=5.
%C A340650 See A337330 for the number of 6-gon to k-gon contacts, with k>=6.
%C A340650 See A007678 for the number of regions and images of other n-gons.
%H A340650 Scott R. Shannon, <a href="/A340650/a340650.png">Image for n = 19</a>. This is the first n-gon with 7-gon to 7-gon contacts.
%H A340650 Scott R. Shannon, <a href="/A340650/a340650_1.png">Image for n = 59</a>. This is the first n-gon with 7-gon to 8-gon contacts.
%e A340650 a(19) = 19, a(20-51) = 0, a(52) = 52, a(53-58) = 0.
%e A340650 The table from a(59) begins:
%e A340650 0, 118,
%e A340650 9;
%e A340650 61;
%e A340650 0;
%e A340650 63;
%e A340650 0;
%e A340650 0;
%e A340650 0;
%e A340650 0;
%e A340650 0;
%e A340650 138;
%e A340650 70;
%e A340650 0;
%e A340650 72;
%e A340650 73;
%e A340650 148;
%e A340650 0;
%e A340650 0;
%e A340650 0;
%e A340650 0;
%e A340650 158;
%e A340650 80;
%e A340650 0;
%e A340650 82;
%e A340650 83;
%e A340650 0;
%e A340650 0;
%e A340650 172;
%e A340650 0;
%e A340650 0;
%e A340650 178;
%e A340650 540;
%e A340650 0;
%e A340650 0;
%e A340650 93, 0, 93;
%e A340650 282;
%e A340650 95;
%e A340650 96;
%e A340650 194;
%e A340650 294;
%e A340650 0, 198, 99;
%e A340650 0;
%Y A340650 Cf. A333654 (3-gon contacts), A335614 (4-gon contacts),  A335646 (5-gon contacts), A337330 (6-gon contacts), A007678, A135565, A007569, A062361, A331450, A331451.
%K A340650 nonn,tabf
%O A340650 19,1
%A A340650 _Scott R. Shannon_, Jan 14 2021