Number of permutations of [n] having two cycles of the form (c1, c2, ..., c_m) where c1 = min_{i>=1} c_i and c_j = min_{i>=j} c_i or c_j = max_{i>=j} c_i.
A346317
Number of permutations of [n] having two cycles of the form (c1, c2, ..., c_m) where c1 = min_{i>=1} c_i and c_j = min_{i>=j} c_i or c_j = max_{i>=j} c_i.
Terms
- a(0) =1a(1) =3a(2) =11a(3) =40a(4) =148a(5) =560a(6) =2160a(7) =8448a(8) =33344a(9) =132352a(10) =527104a(11) =2103296a(12) =8401920a(13) =33583104a(14) =134279168a(15) =537001984a(16) =2147762176a(17) =8590524416a(18) =34360983552a(19) =137441574912a(20) =549761318912
External references
- oeis: A346317