# A331528 (b-file synthesized from sequence entry) 0 0 1 1 2 21 3 156 4 700 5 2325 6 6321 7 14896 8 31536 9 61425 10 111925 11 193116 12 318396 13 505141 14 775425 15 1156800 16 1683136 17 2395521 18 3343221 19 4584700 20 6188700 21 8235381 22 10817521 23 14041776 24 18030000 25 22920625 26 28870101 27 36054396 28 44670556 29 54938325 30 67101825 31 81431296 32 98224896