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Number of even cycles in range [A014137(2n-1)..A014138(2n-1)] of permutation A057505/A057506.
5

%I #10 Jan 11 2024 09:19:11

%S 0,1,3,18,95,528,2936,16212,90717,516358,2979992

%N Number of even cycles in range [A014137(2n-1)..A014138(2n-1)] of permutation A057505/A057506.

%C Equal to the number of all cycles in the same range (after n>0).

%F a(n) = A081150(2n) = A081158(n)+A001700(n-1) [where A001700(-1) is taken as 0 here] = A057507(2n) [After n>0].

%Y Cf. A081152.

%Y Cf. A081150, A081158, A001700, A057507.

%Y Cf. A014137, A014138, A057505, A057506.

%K nonn,more

%O 0,3

%A _Wouter Meeussen_ and _Antti Karttunen_, Mar 10 2003