A333654 Irregular table read by rows: row n gives the number of 3-gon to k-gon contacts, with k>=3, for a regular n-gon with all diagonals drawn.
0, 4, 10, 0, 5, 18, 12, 28, 14, 21, 0, 7, 56, 48, 54, 54, 54, 36, 0, 0, 9, 180, 160, 30, 88, 154, 88, 88, 0, 0, 0, 0, 11, 240, 336, 130, 260, 299, 182, 0, 104, 0, 0, 0, 0, 13, 266, 616, 266, 180, 600, 375, 300, 90, 0, 0, 0, 0, 0, 0, 0, 15, 448, 1056, 320, 256
Offset: 3
Examples
The table begins: . 0; 4; 10,0,5; 18,12; 28,14,21,0,7; 56,48; 54,54,54,36,0,0,9; 180,160,30; 88,154,88,88,0,0,0,0,11; 240,336; 130,260,299,182,0,104,0,0,0,0,13; 266,616,266; 180,600,375,300,90,0,0,0,0,0,0,0,15; 448,1056,320,256; 238,816,935,578,85,238,0,0,0,0,0,0,0,0,17; 900,1836,324,108,126; 304,1520,1463,798,304,228,0,0,0,0,0,0,0,0,0,0,19; 1000,2120,1740,560,0,160; 378,2352,2016,1554,84,0,0,0,0,0,0,0,0,0,0,0,0,0,21; 1056,3828,2310,308,176,220; 460,2852,4117,2530,644,138,0,0,0,0,0,0,0,0,0,0,0,0,0,0,23; 2352,5856,2376,288; 550,4550,4800,3350,900,250,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,25; 1950,6708,5772,1612,650,208; 648,6372,6399,4968,432,810,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,27; 2380,10024,5712,3584,616,224; 754,8642,8497,6148,783,928,0,870,232,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,29; 6330,14640,5340,2340; 868,11532,11191,7378,806,1302,0,496,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,31; 3712,16384,12000,6016,1248; 990,14454,14619,12540,2079,1782,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,33;
Links
- Scott R. Shannon, Image for n=4 with edge-count coloring. This is the first n-gon with 3-gon to 3-gon contacts.
- Scott R. Shannon, Image for n=6 with edge-count coloring. This is the first n-gon with 3-gon to 4-gon contacts.
- Scott R. Shannon, Image for n=7 with edge-count coloring. This is the first n-gon with 3-gon to 5-gon contacts, other than n=5 which has an internal 5-gon surrounded by 3-gons by its construction.
- Scott R. Shannon, Image for n=9 with edge-count coloring. This is the first n-gon with 3-gon to 6-gon contacts.
- Scott R. Shannon, Image for n=15 with edge-count coloring. This is the first n-gon with 3-gon to 7-gon contacts, other than n=7 which has an internal 7-gon surrounded by 3-gons by its construction.
- Scott R. Shannon, Image for n=15 with random distance-based coloring.
- Scott R. Shannon, Image for n=13 with edge-count coloring. This is the first n-gon with 3-gon to 8-gon contacts.
- Scott R. Shannon, Image for n=29 with edge-count coloring. This is the first n-gon with 3-gon to 10-gon and 3-gon to 11-gon contacts.
Crossrefs
Formula
For odd n, with n > 3, row(n,n) = n as the n-gon contains a smaller n-gon at its center surrounded by 3-gons.
Comments