A361361 Triangle read by rows: T(n,k) is the number of bicolored cubic graphs on 2n unlabeled vertices with k vertices of the first color, n >= 0, 0 <= k <= 2*n.
1, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 5, 5, 5, 2, 2, 6, 11, 33, 48, 66, 48, 33, 11, 6, 21, 68, 257, 556, 950, 1071, 950, 556, 257, 68, 21, 94, 510, 2443, 7126, 15393, 23644, 27606, 23644, 15393, 7126, 2443, 510, 94, 540, 4712, 27682, 102122, 270957, 526783, 781292, 887305, 781292, 526783, 270957, 102122, 27682, 4712, 540
Offset: 0
Examples
Triangle begins: 1 0, 0, 0; 1, 1, 1, 1, 1; 2, 2, 5, 5, 5, 2, 2; 6, 11, 33, 48, 66, 48, 33, 11, 6; 21, 68, 257, 556, 950, 1071, 950, 556, 257, 68, 21; ...
Links
- Andrew Howroyd, Table of n, a(n) for n = 0..440 (rows 0..20)
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