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.

Showing 1-4 of 4 results.

A303118 Array read by antidiagonals: T(m,n) = number of minimal total dominating sets in the grid graph P_m X P_n.

Original entry on oeis.org

0, 1, 1, 2, 4, 2, 1, 4, 4, 1, 2, 16, 6, 16, 2, 4, 16, 49, 49, 16, 4, 3, 49, 66, 169, 66, 49, 3, 4, 81, 225, 576, 576, 225, 81, 4, 8, 169, 640, 2601, 2622, 2601, 640, 169, 8, 9, 324, 1681, 10000, 14400, 14400, 10000, 1681, 324, 9, 10, 625, 4641, 38416, 81055, 137641, 81055, 38416, 4641, 625, 10
Offset: 1

Views

Author

Andrew Howroyd, Apr 18 2018

Keywords

Examples

			Table begins:
=============================================================
m\n| 1   2    3     4      5       6         7          8
---+---------------------------------------------------------
1  | 0   1    2     1      2       4         3          4 ...
2  | 1   4    4    16     16      49        81        169 ...
3  | 2   4    6    49     66     225       640       1681 ...
4  | 1  16   49   169    576    2601     10000      38416 ...
5  | 2  16   66   576   2622   14400     81055     440896 ...
6  | 4  49  225  2601  14400  137641   1081600    8185321 ...
7  | 3  81  640 10000  81055 1081600  11458758  125955729 ...
8  | 4 169 1681 38416 440896 8185321 125955729 1944369025 ...
...

Links

Crossrefs

Rows 1..2 are A302655, A303072.
Main diagonal is A303161.
Cf. A300358, A303111, A303293.

A332390 Array read by antidiagonals: T(m,n) is the number of minimal total dominating sets in the m X n king graph.

Original entry on oeis.org

0, 1, 1, 2, 6, 2, 1, 10, 10, 1, 2, 15, 20, 15, 2, 4, 52, 52, 52, 52, 4, 3, 105, 179, 141, 179, 105, 3, 4, 175, 418, 801, 801, 418, 175, 4, 8, 481, 1167, 2950, 7770, 2950, 1167, 481, 8, 9, 1028, 3498, 9792, 34790, 34790, 9792, 3498, 1028, 9, 10, 2000, 9074, 47527, 184318, 204372, 184318, 47527, 9074, 2000, 10
Offset: 1

Views

Author

Andrew Howroyd, Feb 10 2020

Keywords

Examples

			Array begins:
================================================================
m\n | 1   2    3     4       5        6         7          8
----+-----------------------------------------------------------
  1 | 0   1    2     1       2        4         3          4 ...
  2 | 1   6   10    15      52      105       175        481 ...
  3 | 2  10   20    52     179      418      1167       3498 ...
  4 | 1  15   52   141     801     2950      9792      47527 ...
  5 | 2  52  179   801    7770    34790    184318    1305358 ...
  6 | 4 105  418  2950   34790   204372   1593094   14720683 ...
  7 | 3 175 1167  9792  184318  1593094  16260853  231301551 ...
  8 | 4 481 3498 47527 1305358 14720683 231301551 4570906041 ...
  ...

Links

Crossrefs

Rows 1..4 are A302655, A332392, A332393, A332394.
Main diagonal is A332391.
Cf. A286849, A303114, A303118, A303335, A303378.

Formula

T(n,m) = T(m,n).

A300738 Number of minimal total dominating sets in the n-cycle graph.

Original entry on oeis.org

0, 0, 3, 4, 5, 9, 7, 4, 12, 25, 22, 25, 39, 49, 68, 100, 119, 144, 209, 289, 367, 484, 644, 841, 1130, 1521, 1983, 2601, 3480, 4624, 6107, 8100, 10717, 14161, 18807, 24964, 33004, 43681, 57918, 76729, 101639, 134689, 178364, 236196, 313007, 414736, 549289
Offset: 1

Views

Author

Andrew Howroyd, Apr 15 2018

Keywords

Links

Crossrefs

Cf. A001608, A001638 (total dominating sets), A253413, A302653, A302655, A302918.

Programs

  • Mathematica
    Table[RootSum[-1 - # + #^3 &, #^n &] + (1 + (-1)^n) RootSum[-1 + #^2 + #^3 &, #^(n/2) &], {n, 20}]
Perrin[n_] := RootSum[-1 - # + #^3 &, #^n &]; Table[With[{b = Mod[n, 2, 1]}, Perrin[n/b]^b], {n, 20}]
LinearRecurrence[{0, 0, 1, 1, 1, 1, 0, -1, -1}, {0, 0, 3, 4, 5, 9, 7, 4, 12}, 20]
CoefficientList[Series[x^2 (3 + 4 x + 5 x^2 + 6 x^3 - 8 x^5 - 9 x^6)/(1 - x^3 - x^4 - x^5 - x^6 + x^8 + x^9), {x, 0, 20}], x]
  • PARI
    concat([0,0], Vec((3 + 4*x + 5*x^2 + 6*x^3 - 8*x^5 - 9*x^6)/((1 - x^2 - x^3)*(1 + x^2 - x^6)) + O(x^50)))

Formula

a(n) = a(n-3) + a(n-4) + a(n-5) + a(n-6) - a(n-8) - a(n-9) for n > 9.
G.f.: x^3*(3 + 4*x + 5*x^2 + 6*x^3 - 8*x^5 - 9*x^6)/((1 - x^2 - x^3)*(1 + x^2 - x^6)).
a(2*n) = A001608(n)^2.
a(2*n-1) = A001608(2*n-1), where A001608 are the Perrin numbers.

A302654 Number of minimum total dominating sets in the n-path graph.

Original entry on oeis.org

0, 1, 2, 1, 1, 4, 3, 1, 2, 9, 4, 1, 3, 16, 5, 1, 4, 25, 6, 1, 5, 36, 7, 1, 6, 49, 8, 1, 7, 64, 9, 1, 8, 81, 10, 1, 9, 100, 11, 1, 10, 121, 12, 1, 11, 144, 13, 1, 12, 169, 14, 1, 13, 196, 15, 1, 14, 225, 16, 1, 15, 256, 17, 1, 16, 289, 18, 1, 17, 324, 19, 1, 18, 361, 20, 1
Offset: 1

Views

Author

Eric W. Weisstein, Apr 11 2018

Keywords

Links

Crossrefs

Row 1 of A303293.
Cf. A302653, A302655.

Programs

  • Mathematica
    Table[Piecewise[{{1, Mod[n, 4] == 0}, {((n + 2)/4)^2, Mod[n, 4] == 2}, {(n - 1)/4, Mod[n, 4] == 1}, {(n + 5)/4, Mod[n, 4] == 3}}], {n, 20}]
Table[((-1)^n (n - 2)^2 + (6 + n)^2 - 2 (n - 2) (n + 6) Cos[n Pi/2] - 48 Sin[n Pi/2])/64, {n, 20}]
LinearRecurrence[{0, 0, 0, 3, 0, 0, 0, -3, 0, 0, 0, 1}, {0, 1, 2, 1, 1, 4, 3, 1, 2, 9, 4, 1}, 20]
  • PARI
    concat(0, Vec(x^2*(1 + 2*x + x^2 + x^3 + x^4 - 3*x^5 - 2*x^6 - x^7 + x^9 + x^10) / ((1 - x)^3*(1 + x)^3*(1 + x^2)^3) + O(x^70))) \\ Colin Barker, Dec 25 2019

Formula

a(n) = ((-1)^n*(n - 2)^2 + (6 + n)^2 - 2*(n - 2)*(n + 6)*cos(n*Pi/2) - 48*sin(n*Pi/2))/6.
a(n) = 3*a(n-4) - 3*a(n-8) + a(n-12).
G.f.: x^2*(1 + 2*x + x^2 + x^3 + x^4 - 3*x^5 - 2*x^6 - x^7 + x^9 + x^10) / ((1 - x)^3*(1 + x)^3*(1 + x^2)^3). - Colin Barker, Dec 25 2019
E.g.f.: ((12 + x^2)*cos(x) + (20 + 8*x + x^2)*cosh(x) + (5*x - 24)*sin(x) + (16 + 5*x)*sinh(x) - 32)/32. - Stefano Spezia, Jun 10 2025
Showing 1-4 of 4 results.

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