# A086591 (b-file synthesized from sequence entry) 0 1 1 1 2 1 3 1 4 2 5 6 6 24 7 2520 8 18378360 9 6906955255200 10 5987137029832314231356979603166508647200 11 1000156941827668764767034398758639477404906113721462819980559968765060862592344000