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.

A217995 Number of n X 1 arrays of the minimum or maximum value of corresponding elements and their horizontal and vertical neighbors in a random 0..2 n X 1 array.

Original entry on oeis.org

3, 9, 25, 81, 241, 719, 2181, 6543, 19623, 58983, 176995, 531045, 1593739, 4781741, 14346105, 43041933, 129130449, 387399819, 1162223437, 3486708387, 10460197183, 31380761819, 94142587347, 282428344593, 847286292987, 2541861239481
Offset: 1

Views

Author

R. H. Hardin, Oct 17 2012

Keywords

Comments

Column 1 of A217999.

Examples

			Some solutions for n=3:
..1....2....0....0....2....1....1....1....2....1....0....2....2....0....2....1
..0....2....2....2....2....2....2....1....0....1....2....0....2....0....1....0
..1....2....0....1....1....0....2....2....2....0....2....0....0....1....2....0

Links

Crossrefs

Cf. A217999.

Formula

Empirical: a(n) = 3*a(n-1) + a(n-2) + 2*a(n-3) - 13*a(n-4) - 7*a(n-5) + 3*a(n-6).
Empirical g.f.: x*(3 - 5*x^2 - 9*x^3 - 6*x^4 + 3*x^5) / ((1 - 3*x)*(1 - x^2 - 5*x^3 - 2*x^4 + x^5)). - Colin Barker, Jul 23 2018

A217996 Number of nX3 arrays of the minimum or maximum value of corresponding elements and their horizontal and vertical neighbors in a random 0..2 nX3 array.

Original entry on oeis.org

25, 729, 19665, 531143, 14345273, 387332417, 10458051407, 282370309597, 7624012293659, 205848628366997, 5557913837745823, 150063732111219045, 4051720943493086779, 109396471194812694909
Offset: 1

Views

Author

R. H. Hardin Oct 17 2012

Keywords

Comments

Column 3 of A217999

Examples

			Some solutions for n=3
..0..1..0....0..0..1....1..2..0....2..1..2....1..2..0....2..2..1....2..0..2
..0..2..2....1..2..1....1..2..0....0..0..1....2..2..2....2..1..2....0..1..1
..1..1..1....1..1..0....1..1..0....2..0..0....0..0..2....2..2..2....0..0..2

A217997 Number of nX4 arrays of the minimum or maximum value of corresponding elements and their horizontal and vertical neighbors in a random 0..2 nX4 array.

Original entry on oeis.org

81, 6561, 531143, 43046713, 3486751263, 282429513233, 22876783667859, 1853020148203325
Offset: 1

Views

Author

R. H. Hardin Oct 17 2012

Keywords

Comments

Column 4 of A217999

Examples

			Some solutions for n=3
..0..0..2..1....0..0..0..1....0..0..1..2....0..2..0..0....0..0..0..2
..0..2..2..2....0..1..1..0....0..2..0..0....1..0..1..1....0..2..2..1
..2..1..0..2....0..0..2..0....0..1..1..1....1..2..2..2....0..0..2..2

A217998 Number of nX5 arrays of the minimum or maximum value of corresponding elements and their horizontal and vertical neighbors in a random 0..2 nX5 array.

Original entry on oeis.org

241, 59049, 14345273, 3486751263, 847279307713
Offset: 1

Views

Author

R. H. Hardin Oct 17 2012

Keywords

Comments

Column 5 of A217999

Examples

			Some solutions for n=3
..0..0..0..0..1....0..1..2..0..2....0..2..2..1..1....0..0..1..1..0
..0..0..0..1..1....0..0..2..1..1....0..0..0..0..2....0..0..0..1..1
..0..2..2..0..1....0..0..0..2..0....0..1..0..2..0....0..1..0..2..2
Showing 1-4 of 4 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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