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.

A211370 Array read by antidiagonals: T(m,n) = Sum( n <= i <= m+n-1 ) i!.

Original entry on oeis.org

1, 2, 3, 6, 8, 9, 24, 30, 32, 33, 120, 144, 150, 152, 153, 720, 840, 864, 870, 872, 873, 5040, 5760, 5880, 5904, 5910, 5912, 5913, 40320, 45360, 46080, 46200, 46224, 46230, 46232, 46233, 362880, 403200, 408240, 408960, 409080, 409104, 409110, 409112, 409113
Offset: 1

Views

Author

Tilman Piesk, Jul 07 2012

Keywords

Comments

When the numbers denote finite permutations (as row numbers of A055089) these are the circular shifts to the left within an interval. The subsequence A007489 then denotes the circular shifts that start with the first element. Compare A051683 for circular shifts to the right. - Tilman Piesk, Apr 29 2017

Examples

			T(3,2) = Sum( 2 <= i <= 4 ) i! = 2! + 3! + 4! = 32.
The array starts:
  1,    2,     6,     24,     120,      720, ...
  3,    8,    30,    144,     840,     5760, ...
  9,   32,   150,    864,    5880,    46080, ...
33,  152,   870,   5904,   46200,   408960, ...
153,  872,  5910,  46224,  409080,  4037760, ...
873, 5912, 46230, 409104, 4037880, 43954560, ...
		

Crossrefs

Cf. A051683 (circular shifts to the right), A007489 (column n=1), A000142 (row m=1).

Programs

  • Mathematica
    Table[Function[m, Sum[ i!, {i, n, m + n - 1}]][k - n + 1], {k, 9}, {n, k, 1, -1}] // Flatten (* Michael De Vlieger, Apr 30 2017 *)