# A037677 (b-file synthesized from sequence entry) 1 1 2 7 3 51 4 360 5 2521 6 17647 7 123531 8 864720 9 6053041 10 42371287 11 296599011 12 2076193080 13 14533351561 14 101733460927 15 712134226491 16 4984939585440 17 34894577098081 18 244262039686567 19 1709834277805971