cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A321352 Triangle T(n,k) giving the number of permutations pi of {1,2,...,n} such that for all i, pi(i) is not in {i, i+1, ..., i+k-1} (mod n), with 0 <= k <= n - 1.

Original entry on oeis.org

1, 2, 1, 6, 2, 1, 24, 9, 2, 1, 120, 44, 13, 2, 1, 720, 265, 80, 20, 2, 1, 5040, 1854, 579, 144, 31, 2, 1, 40320, 14833, 4738, 1265, 264, 49, 2, 1, 362880, 133496, 43387, 12072, 2783, 484, 78, 2, 1, 3628800, 1334961, 439792, 126565, 30818, 6208, 888, 125, 2, 1
Offset: 1

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Author

Peter Kagey, Feb 25 2020

Keywords

Comments

This is A008305 with the rows reversed.
First column is A000142 (factorial numbers).
Second column is A000166 (derangements).
Third column is A000179 (ménage numbers).
Fourth column is A000183 (discordant permutations)

Examples

			Table begins:
       1
       2,      1
       6,      2,     1
      24,      9,     2,     1
     120,     44,    13,     2,    1
     720,    265,    80,    20,    2,   1
    5040,   1854,   579,   144,   31,   2,  1
   40320,  14833,  4738,  1265,  264,  49,  2, 1
  362880, 133496, 43387, 12072, 2783, 484, 78, 2, 1
		

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