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%I #3 Apr 24 2015 11:31:46
%S 1,1,1,1,2,4,8,11,2,35,68,9,252,524,75,2,2994,7161,934,28,68665,
%T 171684,20296,432,3,3013075,7849829,840786,12766,115
%N Irregular triangle read by rows: row n gives number of connected graphs on n nodes with forcing number k (n>=1, k>=0).
%D C. E. Larson and N. Van Cleemput, Forcing Independence, Croatica Chemica Acta, Vol. 86, No. 4, Dec. 2013, 469-475.
%e Triangle begins:
%e 1
%e 1
%e 1 1
%e 2 4
%e 8 11 2
%e 35 68 9
%e 252 524 75 2
%e 2994 7161 934 28
%e 68665 171684 20296 432 3
%e 3013075 7849829 840786 12766 115
%e ...
%K nonn,tabf,more
%O 1,5
%A _N. J. A. Sloane_, Apr 24 2015