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.

A174740 Triangle read by rows, A027293 * an infinite lower triangular matrix with A147843 as the diagonal and the rest zeros.

Original entry on oeis.org

1, 1, 2, 2, 2, 0, 3, 4, 0, 0, 5, 6, 0, 0, -5, 7, 10, 0, 0, -5, 0, 11, 14, 0, 0, -10, 0, -7, 15, 22, 0, 0, -15, 0, -7, 0, 22, 30, 0, 0, -25, 0, -14, 0, 0, 30, 44, 0, 0, -35, 0, -21, 0, 0, 0, 42, 60, 0, 0, -55, 0, -35, 0, 0, 0, 0, 56, 84, 0, 0, -75, 0, -49, 0, 0, 0, 0, 12
Offset: 1

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Author

Gary W. Adamson, Mar 28 2010

Keywords

Comments

Left border = the partition numbers, A000041; right border = A147843 starting (1, 2, 0, ...).
Row sums apparently give A000203. Check: Sum of row 6 terms = [7, 5, 3, 2, 1, 1] dot [1, 2, 0, 0, -5, 0] = [7 + 10 + 0 + 0 -5 + 0] = 12 = A000203(6).

Examples

			First few rows of the triangle:
   1;
   1,   2;
   2,   2,   0;
   3,   4,   0,   0;
   5,   6,   0,   0,  -5;
   7,  10,   0,   0,  -5,   0;
  11,  14,   0,   0, -10,   0,  -7;
  15,  22,   0,   0, -15,   0,  -7,   0;
  22,  30,   0,   0, -25,   0, -14,   0,   0;
  30,  44,   0,   0, -35,   0, -21,   0,   0,   0;
  42,  60,   0,   0, -55,   0, -35,   0,   0,   0,   0;
  56,  84,   6,   0, -75,   0, -49,   0,   0,   0,   0,  12;
  ...
		

Crossrefs

Formula

Equals triangle A027293 * a lower triangular matrix with A147843 (deleting the first zero) as the right border and the rest zeros.
T(n,k) = A147843(k) * A027293(n,k). - Joerg Arndt, Dec 29 2022

Extensions

Terms corrected by Gary W. Adamson, Dec 27 2022