# A007174 (b-file synthesized from sequence entry) 1 1 2 1 3 1 4 3 5 7 6 20 7 131 8 815 9 5142 10 36800 11 272093 12 2077909 13 16176607 14 127997683 15 1025727646 16 8310377815 17 68217725764 18 560527576100 19 4556993996246