A086624 Main diagonal of square table A086623 of coefficients of f(x,y) that satisfies f(x,y) = (1-xy)/[(1-x)(1-y)] + xy*f(x,y)^2.
1, 1, 4, 19, 100, 570, 3442, 21685, 141112, 941990, 6419174, 44493000, 312818326, 2226155632, 16008452202, 116167346499, 849724397580, 6259403310366, 46399703925202, 345894094030552
Offset: 0