# A371157 (b-file synthesized from sequence entry) 0 1 1 0 2 0 3 6 4 36 5 160 6 1620 7 18648 8 220080 9 2924640 10 44775360 11 753207840 12 13836731040 13 276442882560 14 5972081379264 15 138607594171200 16 3440465206214400 17 90951997553464320 18 2551374460670538240 19 75694365919478960640 20 2368107785432883916800