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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A268908 Number of 5 X n 0..2 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two exactly once.

Original entry on oeis.org

0, 6912, 98496, 1347192, 17194680, 214142760, 2611960344, 31382176824, 372469407912, 4376985056856, 51011490408120, 590386685589432, 6792451934064264, 77748739088317848, 885979967930009496
Offset: 1

Views

Author

R. H. Hardin, Feb 15 2016

Keywords

Comments

Row 5 of A268904.

Examples

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

Links

Crossrefs

Cf. A268904.

Formula

Empirical: a(n) = 32*a(n-1) -384*a(n-2) +2200*a(n-3) -6494*a(n-4) +9016*a(n-5) -816*a(n-6) -14888*a(n-7) +18879*a(n-8) -5464*a(n-9) -7472*a(n-10) +8336*a(n-11) -3648*a(n-12) +768*a(n-13) -64*a(n-14) for n>18.

A268909 Number of 6Xn 0..2 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two exactly once.

Original entry on oeis.org

0, 33792, 715392, 14644152, 282550680, 5344944120, 99308573208, 1821165633864, 33033242938536, 593761996675728, 10591066349377632, 187684309946743128, 3307315733915348808, 57997191529735867080, 1012715407159459735536
Offset: 1

Views

Author

R. H. Hardin, Feb 15 2016

Keywords

Comments

Row 6 of A268904.

Examples

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

Links

Crossrefs

Cf. A268904.

Formula

Empirical: a(n) = 60*a(n-1) -1466*a(n-2) +19056*a(n-3) -143515*a(n-4) +608478*a(n-5) -957350*a(n-6) -3924114*a(n-7) +27201539*a(n-8) -68079378*a(n-9) +46537423*a(n-10) +212613240*a(n-11) -785654632*a(n-12) +1389943104*a(n-13) -1544105168*a(n-14) +1125401088*a(n-15) -524553472*a(n-16) +142135296*a(n-17) -17040384*a(n-18) for n>26

A268910 Number of 7Xn 0..2 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling two exactly once.

Original entry on oeis.org

0, 159744, 5038848, 154472184, 4513169016, 129834259704, 3679171151832, 103095286509168, 2860978283523432, 78747017051741472, 2152203067541169000, 58462727175138511872, 1579670961301113123600, 42485047384554878027688
Offset: 1

Views

Author

R. H. Hardin, Feb 15 2016

Keywords

Comments

Row 7 of A268904.

Examples

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

Links

Crossrefs

Cf. A268904.

Formula

Empirical recurrence of order 54 (see link above)
Previous Showing 11-13 of 13 results.

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