a(n) = 2(m!)^2 for n = 2m and m!(m+1)! for n = 2m+1.
2, 1, 2, 2, 8, 12, 72, 144, 1152, 2880, 28800, 86400, 1036800, 3628800, 50803200
2 seqfan posts
Thu Aug 12 15:14:15 CEST 2010 [seqfan] Re: Permutations: sum of max of each adjacent pair
Thu Aug 12 01:47:44 CEST 2010 [seqfan] Permutations: sum of max of each adjacent pair
Index of A-numbers in seqfan: by ascending order
by month
by frequency
by keyword
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