A185133 Number of not necessarily connected 3-regular simple graphs on 2n vertices with girth exactly 3.
0, 0, 1, 1, 4, 15, 71, 428, 3406, 34270, 418621, 5937051, 94782437, 1670327647, 32090011476, 666351752261, 14859579573845
Offset: 0
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.
2: 0; 3: 0; 4: 0, 0; 5: 0, 0; 6: 0, 0, 1; 7: 0, 0, 1; 8: 0, 0, 1, 1; 9: 0, 0, 2, 0; 10: 0, 0, 2, 2, 1; 11: 0, 0, 3, 0, 1; 12: 0, 0, 4, 8, 3, 1; 13: 0, 0, 5, 0, 8, 0; 14: 0, 0, 6, 29, 25, 3, 1; 15: 0, 0, 9, 0, 88, 0, 1; 16: 0, 0, 10, 138, 377, 66, 5, 1; 17: 0, 0, 13, 0, 2026, 0, 25, 0; 18: 0, 0, 17, 774, 13349, 8029, 297, 5, 1; 19: 0, 0, 21, 0, 104593, 0, 8199, 0, 1; 20: 0, 0, 25, 5678, 930571, 3484759, 377004, 1562, 7, 1; 21: 0, 0, 33, 0, 9124627, 0, 22014143, 0, 100, 0; 22: 0, 0, 39, 53324, 96699740, 2595985769, 1493574756, 21617036, 10901, 9, 1; 23: 0, 0, 49, 0, 1095467916, 0, 114880777582, 0, 3470736, 0, 1; 24: 0, 0, 60, 622716, 13175254799, 2815099031409, 9919463450854, 733460349818, 1473822243, 88238, 11, 1;