A360866
Triangle read by rows: T(n,k) is the number of unlabeled connected loopless multigraphs with n edges on k nodes and degree >= 3 at each node, n >= 2, 1 <= k <= floor(2*n/3).
Original entry on oeis.org
0, 0, 1, 0, 1, 0, 1, 1, 0, 1, 3, 2, 0, 1, 4, 7, 0, 1, 6, 19, 6, 0, 1, 8, 40, 37, 6, 0, 1, 10, 71, 135, 56, 0, 1, 12, 117, 366, 338, 35, 0, 1, 15, 184, 858, 1417, 494, 20, 0, 1, 17, 270, 1778, 4670, 3494, 492, 0, 1, 20, 387, 3413, 13125, 17355, 6047, 251
Offset: 2
Triangle begins:
0;
0, 1;
0, 1;
0, 1, 1;
0, 1, 3, 2;
0, 1, 4, 7;
0, 1, 6, 19, 6;
0, 1, 8, 40, 37, 6;
0, 1, 10, 71, 135, 56;
0, 1, 12, 117, 366, 338, 35;
0, 1, 15, 184, 858, 1417, 494, 20;
0, 1, 17, 270, 1778, 4670, 3494, 492;
0, 1, 20, 387, 3413, 13125, 17355, 6047, 251;
...
A360868
Number of unlabeled connected loopless multigraphs with circuit rank n and degree >= 3 at each node.
Original entry on oeis.org
0, 1, 4, 23, 172, 1848, 25684
Offset: 1
A360871
Number of unlabeled nonseparable (or 2-connected) multigraphs with n edges and degree >= 3 at each node, loops allowed.
Original entry on oeis.org
0, 0, 2, 4, 9, 20, 44, 113, 329, 1044, 3622, 13544, 53596, 223084, 969158
Offset: 1
The a(3) = 2 multigraphs are:
- a triple edge;
- a single edge with a loop at each vertex.
A360869
Number of unlabeled loopless multigraphs with n edges and degree >= 3 at each node.
Original entry on oeis.org
0, 0, 1, 1, 2, 7, 13, 35, 101, 295, 928, 3168, 11247, 42263
Offset: 1
A360882
Number of unlabeled connected multigraphs with n edges, no cut-points and degree >= 3 at each node, loops allowed.
Original entry on oeis.org
0, 1, 3, 5, 10, 21, 45, 114, 330, 1045, 3623, 13545, 53597, 223085, 969159
Offset: 1
The a(3) = 3 multigraphs are:
- a single vertex with 3 loops;
- a triple edge;
- a single edge with a loop at each vertex.
Showing 1-5 of 5 results.
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