Number of permutations of 1..n with both permutation and its inverse having exactly 2 maxima.
A180392
Number of permutations of 1..n with both permutation and its inverse having exactly 2 maxima.
Terms
- a(0) =0a(1) =0a(2) =1a(3) =12a(4) =66a(5) =248a(6) =739a(7) =1880a(8) =4260a(9) =8832a(10) =17061a(11) =31108a(12) =54054a(13) =90168a(14) =145223a(15) =226864
External references
- oeis: A180392