A038023 Triangle: T(n,k), k<=n: commutative groupoids with a nontrivial symmetry with n elements and k idempotents.
0, 0, 0, 0, 0, 0, 3, 6, 0, 4, 96, 214, 128, 64, 38, 54248, 83925, 54223, 28254, 10223, 1894
Offset: 0
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