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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A202471 T(n,k) = Number of (n+2) X (k+2) binary arrays with no more than two of any consecutive three bits set in any row or column.

Original entry on oeis.org

265, 1573, 1573, 9253, 16561, 9253, 54085, 172197, 172197, 54085, 317179, 1774281, 3157010, 1774281, 317179, 1858993, 18374521, 57262144, 57262144, 18374521, 1858993, 10894297, 190112777, 1044865367, 1828904402, 1044865367, 190112777, 10894297
Offset: 1

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Author

R. H. Hardin, Dec 19 2011

Keywords

Examples

			Table starts
......265........1573..........9253............54085.............317179
.....1573.......16561........172197..........1774281...........18374521
.....9253......172197.......3157010.........57262144.........1044865367
....54085.....1774281......57262144.......1828904402........58746383721
...317179....18374521....1044865367......58746383721......3323590649777
..1858993...190112777...19045287529....1885066867201....187820723381421
.10894297..1966463785..347030298362...60472625443366..10610932604054547
.63850777.20345296193.6325139804762.1940390570621922.599616560193259281
...
Some solutions for n=1, k=3
..0..1..1..0..1....0..1..0..1..0....0..0..0..0..0....1..1..0..1..0
..0..0..1..0..0....1..0..0..0..1....1..0..0..1..0....1..1..0..0..0
..0..0..0..0..1....1..1..0..1..0....0..1..0..0..0....0..0..0..0..1
		

Crossrefs

Diagonal is A050974(n+2), col/row 1 is A202464, col/row 2 is A202465, col/row 3 is A202466.

A067968 Number of binary arrangements on n X n array without adjacent three 1's.

Original entry on oeis.org

1, 2, 11, 163, 6547, 720417, 216173426, 177509416175, 398239490006383, 2441922679051541299, 40923800121824894177005, 1874434223405139511637099884, 234647514833189124245764389957097, 80281172893810827268371440460572492150
Offset: 0

Views

Author

R. H. Hardin, Feb 02 2002

Keywords

References

  • Steven R. Finch, Mathematical Constants, Cambridge, 2003, pp. 342-349.

Crossrefs

Adjacent three in a row or column gives A050974.

Extensions

a(13) from Sean A. Irvine, Jan 15 2024
a(0)=1 prepended by Alois P. Heinz, Sep 26 2024
Showing 1-2 of 2 results.