Triangle read by rows: For n >= 0, k >= 0, T(n,k) is the number of permutations pi of n such that the total distance Sum_i abs(i-pi(i)) = 2k. Equivalently, k = Sum_i max(i-pi(i),0).
A062869
Triangle read by rows: For n >= 0, k >= 0, T(n,k) is the number of permutations pi of n such that the total distance Sum_i abs(i-pi(i)) = 2k. Equivalently, k = Sum_i max(i-pi(i),0).
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =2a(6) =3a(7) =1a(8) =3a(9) =7a(10) =9a(11) =4a(12) =1a(13) =4a(14) =12a(15) =24a(16) =35a(17) =24a(18) =20a(19) =1a(20) =5a(21) =18a(22) =46a(23) =93a(24) =137a(25) =148a(26) =136a(27) =100a(28) =36a(29) =1
External references
- oeis: A062869