# A037552 (b-file synthesized from sequence entry) 1 2 2 7 3 22 4 68 5 205 6 616 7 1850 8 5551 9 16654 10 49964 11 149893 12 449680 13 1349042 14 4047127 15 12141382 16 36424148 17 109272445 18 327817336 19 983452010 20 2950356031 21 8851068094 22 26553204284 23 79659612853 24 238978838560 25 716936515682