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.

User: Stephan Mertens

Stephan Mertens's wiki page.

Stephan Mertens has authored 5 sequences.

A375603 Array read by antidiagonals: T(m,n) = domination number of the stacked prism graph C_m X P_n.

Original entry on oeis.org

1, 1, 1, 1, 2, 1, 2, 2, 2, 2, 2, 3, 3, 2, 2, 2, 3, 4, 3, 3, 2, 3, 4, 4, 4, 4, 4, 3, 3, 4, 5, 5, 6, 5, 4, 3, 3, 5, 6, 6, 7, 6, 6, 4, 3, 4, 5, 7, 7, 8, 8, 7, 6, 5, 4, 4, 6, 7, 8, 9, 9, 9, 8, 7, 6, 4, 4, 6, 8, 9, 10, 10, 11, 10, 10, 8, 6, 4, 5, 7, 9, 10, 11, 12, 12, 12, 12, 10, 9, 6, 5
Offset: 1

Author

Stephan Mertens, Aug 20 2024

Keywords

Examples

			Table starts:
====================================
m\n |   1   2   3    4    5    6 ...
----|-------------------------------
  1 |   1   1   1    2    2    2 ...
  2 |   1   2   2    3    3    4 ...
  3 |   1   2   3    4    4    5 ...
  4 |   2   2   3    4    5    6 ...
  5 |   2   3   4    6    7    8 ...
  6 |   2   4   5    6    8    9 ...
 ...
		

Crossrefs

Main diagonal is A375601.

A375601 a(n) = domination number of the stacked prism graph C_n X P_n.

Original entry on oeis.org

1, 2, 3, 4, 7, 9, 12, 16, 20, 24, 28, 34, 40, 45, 51, 58, 65, 73, 81, 88, 98, 107, 117, 127
Offset: 1

Author

Stephan Mertens, Aug 20 2024

Keywords

Crossrefs

Main diagonal of A375603.
Cf. A375569.

A375566 Array read by antidiagonals: T(m,n) = number of minimum dominating sets in the stacked prism graph C_m X P_n.

Original entry on oeis.org

1, 2, 2, 1, 6, 3, 4, 3, 9, 6, 3, 12, 34, 4, 5, 1, 2, 123, 4, 10, 3, 8, 17, 3, 16, 5, 51, 14, 4, 2, 18, 28, 290, 18, 14, 8, 1, 20, 93, 76, 320, 6, 63, 4, 3, 13, 2, 438, 164, 265, 171, 14, 4, 18, 25, 5, 24, 3, 396, 255, 36, 91, 24, 9, 120, 11, 1, 2, 27, 904, 250, 6, 1526, 60, 2052, 25, 22, 3
Offset: 1

Author

Stephan Mertens, Aug 19 2024

Keywords

Examples

			Table starts:
====================================
m\n |   1   2   3    4    5    6 ...
----+-------------------------------
  1 |   1   2   1    4    3    1 ...
  2 |   2   6   3   12    2   17 ...
  3 |   3   9  34  123    3   18 ...
  4 |   6   4   4   16   28   76 ...
  5 |   5  10   5  290  320  265 ...
 ...
		

Crossrefs

Main diagonal is A375569.
Rows 1..2 are A347633, A347558.
Column 1 is A347538, column 2 is essentially A347634.

A375569 a(n) = number of minimum dominating sets in the stacked prism graph C_n X P_n.

Original entry on oeis.org

1, 6, 34, 16, 320, 36, 56, 5556, 20196, 32210, 88, 121428, 388284, 224, 1489960, 12800, 251464, 2304, 36784, 73062090, 29787744, 738959760, 73600, 884736
Offset: 1

Author

Stephan Mertens, Aug 19 2024

Keywords

Crossrefs

Main diagonal of A375566.

A368831 Irregular triangle read by rows: T(n,k) is the number of dominating subsets with cardinality k of the n X n rook graph (n >= 0, 0 <= k <= n^2).

Original entry on oeis.org

1, 0, 1, 0, 0, 6, 4, 1, 0, 0, 0, 48, 117, 126, 84, 36, 9, 1, 0, 0, 0, 0, 488, 2640, 6712, 10864, 12726, 11424, 8008, 4368, 1820, 560, 120, 16, 1, 0, 0, 0, 0, 0, 6130, 58300, 269500, 808325, 1778875, 3075160, 4349400, 5154900, 5186300, 4454400, 3268360, 2042950, 1081575, 480700, 177100, 53130, 12650, 2300, 300, 25, 1
Offset: 0

Author

Stephan Mertens, Jan 07 2024

Keywords

Comments

The entries in row n are the coefficients of the domination polynomial of the n X n rook graph.
Sum of entries in row n = A287065 = main diagonal of A287274.
Number of minimum dominating sets T(n,n) = A248744(n).

Examples

			Triangle begins: (first 5 rows)
  1;
  0, 1;
  0, 0, 6,  4,   1;
  0, 0, 0, 48, 117,  126,   84,    36,     9,     1;
  0, 0, 0,  0, 488, 2640, 6712, 10864, 12726, 11424, 8008, 4368, 1820, 560, 120, 16, 1;
  ...
		

References

  • John J. Watkins, Across the Board: The Mathematics of Chessboard Problems, Princeton University Press, 2004, chapter 7.

Crossrefs

Cf. A000290, A083374, A287065 (row sums), A287274, A248744 (leading diagonal).

Programs

  • Mathematica
    R[n_, m_] := CoefficientList[((x + 1)^n - 1)^m - (-1)^m*Sum[Binomial[m, k]*(-1)^k*((1 + x)^k - 1)^n, {k, 0, m - 1}], x];
    Flatten[Table[R[n,n],{n,1,5}]]

Formula

G.f.: ((x+1)^n - 1)^m - (-1)^m * Sum_{k=0..m-1} binomial(m,k)*(-1)^k*((1+x)^k - 1)^n (for the rectangular n X m rook graph).
T(n,n) = 2*n^n - n!.