Number T(n,k) of permutations of [n] having k points that are fixed or reflected; triangle T(n,k), n>=0, 0<=k<=n, read by rows.
A335872
Number T(n,k) of permutations of [n] having k points that are fixed or reflected; triangle T(n,k), n>=0, 0<=k<=n, read by rows.
Terms
- a(0) =1a(1) =0a(2) =1a(3) =0a(4) =0a(5) =2a(6) =0a(7) =4a(8) =0a(9) =2a(10) =4a(11) =0a(12) =16a(13) =0a(14) =4a(15) =16a(16) =36a(17) =32a(18) =32a(19) =0a(20) =4a(21) =80a(22) =192a(23) =216a(24) =128a(25) =96a(26) =0a(27) =8a(28) =672a(29) =1472
External references
- oeis: A335872