# A024962 (b-file synthesized from sequence entry) 1 2 2 4 3 11 4 28 5 68 6 169 7 470 8 1276 9 3395 10 9016 11 26240 12 74017 13 204590 14 568120 15 1659350 16 4770820 17 13538480 18 38435515 19 113673998 20 331360936 21 955040204 22 2757123412 23 8185543376 24 24071728150 25 70215321944 26 204746123776 27 612178795262 28 1813222985320