# A163174 (b-file synthesized from sequence entry) 0 1 1 24 2 552 3 12696 4 291732 5 6703488 6 154034496 7 3539441664 8 81330144060 9 1868823662376 10 42942280730712 11 986738081076264 12 22673505553878564 13 520997277758500752 14 11971601073631152624 15 275086336118245407888