A081159 Number of even cycles in range [A014137(2n)..A014138(2n)] of permutation A057505/A057506, with no fixed points of either A057163 or A057164.
0, 0, 2, 20, 148, 986, 5918, 34708, 202664
Offset: 0
Formula
a(n) = A081157(2n+1).
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