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.

A185909 Accumulation array of A185908, by antidiagonals.

Original entry on oeis.org

1, 2, 3, 3, 7, 6, 4, 11, 14, 10, 5, 15, 23, 23, 15, 6, 19, 32, 38, 34, 21, 7, 23, 41, 54, 56, 47, 28, 8, 27, 50, 70, 80, 77, 62, 36, 9, 31, 59, 86, 105, 110, 101, 79, 45, 10, 35, 68, 102, 130, 145, 144, 128, 98, 55, 11, 39, 77, 118, 155, 181, 190, 182, 158, 119, 66, 12, 43, 86, 134, 180, 217, 238, 240, 224, 191, 142, 78, 13, 47, 95, 150, 205, 253, 287, 301, 295, 270, 227, 167, 91, 14, 51, 104, 166, 230, 289, 336, 364, 370, 355, 320, 266, 194, 105, 15, 55, 113, 182, 255
Offset: 1

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Author

Clark Kimberling, Feb 06 2011

Keywords

Comments

A member of the accumulation chain ... < A185907 < A185908 < A185909 < ...
(See A144112 for definitions of weight array and accumulation array.)

Examples

			Northwest corner:
   1,  2,  3,  4,  5
   3,  7, 11, 15, 19
   6, 14, 23, 32, 41
  10, 23, 38, 54, 70
		

Crossrefs

diag (1,7,...): A004068.
diag (2,11,...): A033994.
diag (3,14,...): A162147.

Programs

  • Mathematica
    f[n_, 0] := 0; f[0, k_] := 0; (*needed for the weight array*)
    f[n_, k_] := Min[n, k] + n - 1;
    s[n_, k_] := Sum[f[i, j], {i, 1, n}, {j, 1, k}];
    Table[s[n - k + 1, k], {n, 10}, {k, n, 1, -1}] // Flatten