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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A183312 T(n,k) = Half the number of n X k binary arrays with no element equal to a strict majority of its horizontal and vertical neighbors.

Original entry on oeis.org

1, 1, 1, 1, 3, 1, 2, 4, 4, 2, 3, 6, 9, 6, 3, 5, 9, 19, 19, 9, 5, 8, 14, 42, 55, 42, 14, 8, 13, 22, 93, 178, 178, 93, 22, 13, 21, 35, 205, 572, 910, 572, 205, 35, 21, 34, 56, 452, 1798, 4212, 4212, 1798, 452, 56, 34, 55, 90, 997, 5700, 19899, 29400, 19899, 5700, 997, 90, 55, 89
Offset: 1

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Author

R. H. Hardin, Jan 03 2011

Keywords

Comments

Same solutions for no element unequal to a strict majority of its horizontal and vertical neighbors, via xor with a 0101... checkerboard pattern.
Table starts
..1..1....1.....2.......3........5..........8..........13............21
..1..3....4.....6.......9.......14.........22..........35............56
..1..4....9....19......42.......93........205.........452...........997
..2..6...19....55.....178......572.......1798........5700.........18064
..3..9...42...178.....910.....4212......19899.......94217........445859
..5.14...93...572....4212....29400.....206755.....1447110......10149621
..8.22..205..1798...19899...206755....2160250....22504107.....234636215
.13.35..452..5700...94217..1447110...22504107...348871589....5406312318
.21.56..997.18064..445859.10149621..234636215..5406312318..124597748299
.34.90.2199.57249.2113257.71244598.2447317278.83828453334.2872365166632

Examples

			Some solutions with a(1,1)=0 for 6 X 6
..0..1..0..1..0..0....0..1..1..0..0..1....0..1..1..0..0..1....0..1..0..1..0..0
..1..1..0..0..1..1....1..0..0..1..1..0....1..0..0..1..1..0....0..1..1..0..1..1
..0..0..1..1..0..0....0..1..0..0..1..0....0..0..1..0..0..1....1..0..1..1..0..0
..1..1..1..0..1..1....0..1..1..0..0..1....1..1..0..1..1..0....0..1..0..0..1..1
..0..0..0..1..0..0....1..0..0..1..0..0....0..1..0..0..1..0....1..0..0..1..0..0
..1..1..0..1..0..1....0..1..1..0..1..1....1..0..1..1..0..1....1..0..1..0..1..1
		

Crossrefs

Column 1 is A000045(n-1) for n>1.
Column 2 is A000045(n+1)+1 for n>1.
Cf. A183304 (col 3), A183305 (col 4), A183306 (col 5), A183307 (col 6), A183308 (col 7), A183309 (col 8).
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