A281446 Triangle read by rows: Number of oriented graphs on n nodes with k components.
1, 0, 1, 0, 1, 1, 0, 5, 1, 1, 0, 34, 6, 1, 1, 0, 535, 39, 6, 1, 1, 0, 20848, 584, 40, 6, 1, 1, 0, 2120098, 21553, 589, 40, 6, 1, 1, 0, 572849763, 2144216, 21602, 590, 40, 6, 1, 1, 0, 415361983540, 575092291, 2144956, 21607, 590, 40, 6, 1, 1, 0, 815590925440865, 415946286005, 575116919, 2145005, 21608
Offset: 0
Examples
1; 0,1; 0,1,1; 0,5,1,1; 0,34,6,1,1; 0,535,39,6,1,1; 0,20848,584,40,6,1,1; 0,2120098,21553,589,40,6,1,1; 0,572849763,2144216,21602,590,40,6,1,1; 0,415361983540,575092291,2144956,21607,590,40,6,1,1;
Formula
G.f.: Product_{j>=1} (1-y*x^j)^(-A086345(j)). - Alois P. Heinz, Apr 13 2017
Comments