# A138379 (b-file synthesized from sequence entry) 1 1 2 6 3 60 4 888 5 18120 6 485280 7 16445520 8 685722240 9 34411184640 10 2041544736000 11 141106965753600 12 11223409849344000 13 1016591564596608000 14 103921686070339737600 15 11896153817325313536000