# A003083 (b-file synthesized from sequence entry) 1 1 2 3 3 7 4 27 5 106 6 681 7 5972 8 88963 9 2349727 10 117165818 11 11073706216 12 1968717966417 13 654366802299848 14 406048824479878828 15 470960717141418629512 16 1023512961811602818909395 17 4179821138595428450831985657 18 32171971054480183600023612728841