# A074408 (b-file synthesized from sequence entry) 1 0 2 1 3 2 4 4 5 11 6 32 7 128 8 512 9 1920 10 6963 11 24576 12 87380 13 317755 14 1179648 15 4438966 16 16777216 17 63406080 18 239541344 19 905969664 20 3435973836 21 13076666409 22 49928994816 23 191126044672 24 733007751680 25 2815436626328 26 10828603699515 27 41705086880768 28 160842843834660