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.

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A281061 Number of 6Xn 0..1 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.

Original entry on oeis.org

0, 468, 4988, 10112, 22106, 46610, 87995, 159317, 282552, 495655, 864369, 1501627, 2601791, 4498333, 7762266, 13369326, 22983871, 39440039, 67556367, 115513187, 197179026, 336035590, 571793109, 971529387, 1648428839, 2793279473
Offset: 1

Views

Author

R. H. Hardin, Jan 13 2017

Keywords

Comments

Row 6 of A281056.

Examples

			Some solutions for n=4
..0..1..0..1. .0..0..1..0. .0..0..1..0. .0..0..1..0. .0..0..1..1
..0..1..0..0. .1..0..1..0. .1..1..0..1. .0..1..0..1. .1..0..0..1
..0..1..1..0. .1..0..1..1. .0..1..0..1. .0..1..0..1. .1..1..0..0
..0..0..0..1. .1..0..1..0. .0..1..0..1. .1..1..0..1. .0..1..1..1
..1..1..0..0. .0..1..0..1. .1..1..0..0. .0..1..0..1. .0..1..0..1
..0..1..1..0. .0..1..0..0. .0..1..1..0. .0..1..0..0. .0..1..1..1

Links

Crossrefs

Cf. A281056.

Formula

Empirical: a(n) = 6*a(n-1) -12*a(n-2) +5*a(n-3) +12*a(n-4) -12*a(n-5) -3*a(n-6) +6*a(n-7) -a(n-9) for n>19

A281062 Number of 7Xn 0..1 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.

Original entry on oeis.org

0, 1686, 15028, 27635, 58005, 119205, 221212, 394884, 689397, 1191475, 2050466, 3523654, 6051629, 10389370, 17827528, 30568529, 52364160, 89595493, 153099429, 261254732, 445190263, 757565887, 1287362382, 2184769552, 3703030677
Offset: 1

Views

Author

R. H. Hardin, Jan 13 2017

Keywords

Comments

Row 7 of A281056.

Examples

			Some solutions for n=4
..0..1..1..0. .0..1..1..0. .0..1..0..1. .0..0..0..1. .0..1..0..1
..0..0..1..0. .1..0..1..0. .0..1..1..0. .1..1..0..1. .0..1..0..1
..1..1..0..1. .1..0..1..0. .0..1..0..1. .0..1..0..1. .0..1..0..0
..0..1..0..1. .0..1..0..1. .0..1..0..0. .0..1..0..1. .0..1..1..0
..1..0..1..0. .0..1..0..1. .1..0..1..1. .0..1..0..0. .0..0..1..0
..1..0..1..0. .1..0..0..1. .1..0..0..1. .1..0..1..1. .1..0..1..0
..0..0..1..0. .0..1..0..1. .1..1..0..1. .1..0..0..1. .1..1..0..0

Links

Crossrefs

Cf. A281056.

Formula

Empirical: a(n) = 6*a(n-1) -12*a(n-2) +5*a(n-3) +12*a(n-4) -12*a(n-5) -3*a(n-6) +6*a(n-7) -a(n-9) for n>20

A281049 Number of n X n 0..1 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.

Original entry on oeis.org

0, 1, 68, 1022, 7803, 46610, 221212, 926077, 3549039, 12749511, 43675963, 144504080, 466130380
Offset: 1

Views

Author

R. H. Hardin, Jan 13 2017

Keywords

Comments

Diagonal of A281056.

Examples

			Some solutions for n=4
..0..1..0..0. .0..1..1..0. .0..1..1..0. .0..1..1..0. .0..1..0..1
..0..1..1..0. .0..0..1..0. .0..0..1..1. .0..1..1..0. .0..1..0..1
..0..0..0..0. .0..1..1..0. .1..0..1..0. .1..0..1..1. .1..0..1..0
..1..0..1..1. .1..0..1..0. .0..0..1..1. .1..0..0..1. .1..1..1..0

Crossrefs

Cf. A281056.
Previous Showing 11-13 of 13 results.

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