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%I #6 Feb 05 2014 20:18:18
%S 1,2,6,8,36,16,127,320,581,1564,13565,13760,149186,773727,540538
%N Number of permutations P of 1..n such that in P and in the inverse of P, every pair of adjacent numbers and the first and last number, are relatively prime.
%C Sequence suggested by _Leroy Quet_ on the SeqFan mailing list.
%e a(4)=8, since the 8 permutations (1,2,3,4), (1,4,3,2), (2,1,4,3), (2,3,4,1), (4,1,2,3), (3,2,1,4), (3,4,1,2), (4,3,2,1) satisfy the property.
%Y Cf. A076220, A117541.
%K nonn
%O 1,2
%A _Giovanni Resta_, Mar 28 2006
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