# A103872 (b-file synthesized from sequence entry) 0 0 1 2 2 2 3 6 4 12 5 30 6 72 7 182 8 464 9 1206 10 3170 11 8426 12 22596 13 61074 14 166194 15 454950 16 1251984 17 3461574 18 9611190 19 26787378 20 74916660 21 210178458 22 591347988 23 1668172842 24 4717282752 25 13369522250 26 37970114702 27 108045430902