# A116753 (b-file synthesized from sequence entry) 1 1 2 2 3 6 4 21 5 73 6 236 7 705 8 1970 9 5224 10 13307 11 32866 12 79251 13 187523 14 437030 15 1005935 16 2291536 17 5174458 18 11596189 19 25816552 20 57141641 21 125822061 22 275766912 23 601872301 24 1308610526 25 2835334908 26 6123666671 27 13186871710 28 28319917295