# A074407 (b-file synthesized from sequence entry) 1 0 2 0 3 0 4 4 5 16 6 53 7 169 8 512 9 1706 10 6144 11 23040 12 87380 13 327680 14 1217097 15 4509419 16 16777216 17 62914560 18 237677216 19 902430720 20 3435973836 21 13102206738 22 50026607709 23 191312873561 24 733007751680 25 2814062572336 26 10823317585920 27 41694904974720 28 160842843834660