A285793 Sum T(n,k) of the k-th entries in all cycles of all permutations of [n]; triangle T(n,k), n>=1, 1<=k<=n, read by rows.
1, 4, 2, 18, 13, 5, 96, 83, 43, 18, 600, 582, 342, 192, 84, 4320, 4554, 2874, 1824, 1068, 480, 35280, 39672, 26232, 17832, 11784, 7080, 3240, 322560, 382248, 261288, 185688, 131256, 88920, 54360, 25200, 3265920, 4044240, 2834640, 2078640, 1534320, 1110960, 765360, 473760, 221760
Offset: 1
Examples
T(3,2) = 13 because the sum of the second entries in all cycles of all permutations of [3] ((123), (132), (12)(3), (13)(2), (1)(23), (1)(2)(3)) is 2+3+2+3+3+0 = 13. Triangle T(n,k) begins: : 1; : 4, 2; : 18, 13, 5; : 96, 83, 43, 18; : 600, 582, 342, 192, 84; : 4320, 4554, 2874, 1824, 1068, 480; : 35280, 39672, 26232, 17832, 11784, 7080, 3240; : 322560, 382248, 261288, 185688, 131256, 88920, 54360, 25200;
Links
- Wikipedia, Permutation
Crossrefs
Formula
T(n,1) = n * n!.
T(n,n) = floor((n-1)!*(n+2)/2).
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