A108243 - cp's OEIS frontend

A108243 a(n) = number of 3-regular (trivalent) multi-graphs without loops on 2n vertices; a(n) = number of symmetric 2n X 2n matrices with {0,1,2,3}-entries with row sum equal to 3 for each row and trace 0.

n	a(n)
0	1
1	1
2	10
3	760
4	190050
5	103050570
6	102359800620
7	168076482974400
8	424343374430075100
9	1560473478516337885500
10	8014685021084051980870200
11	55595731825871742484530751200
12	506777617936508379069463525671000
13	5933390819918520195635187162608235000
14	87521940468361373047495526366554342050000

[1, 1, 10, 760, 190050, 103050570, 102359800620, 168076482974400, 424343374430075100, 1560473478516337885500, 8014685021084051980870200, 55595731825871742484530751200, 506777617936508379069463525671000, 5933390819918520195635187162608235000, 87521940468361373047495526366554342050000]

cp's OEIS Frontend

A108243 a(n) = number of 3-regular (trivalent) multi-graphs without loops on 2n vertices; a(n) = number of symmetric 2n X 2n matrices with {0,1,2,3}-entries with row sum equal to 3 for each row and trace 0.

Table of values

List of values