# A088131 (b-file synthesized from sequence entry) 0 1 1 1 2 8 3 29 4 115 5 452 6 1779 7 7001 8 27552 9 108429 10 426715 11 1679308 12 6608803 13 26008497 14 102354680 15 402809917 16 1585231171 17 6238570004 18 24551470099 19 96620649225 20 380244026896 21 1496424637485 22 5889077900715 23 23176067575964