A181020 - OEIS

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A181020

Maximum number of 1s in an nX(n+1) binary matrix with no three 1s adjacent in a line along a row, column or diagonally.

2, 4, 7, 12, 17, 23, 30, 38, 47, 58

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

LINKS

Table of n, a(n) for n=1..10.

EXAMPLE

Some solutions for 6X7

..1..0..1..0..1..0..1....1..0..1..0..1..0..1....1..0..1..0..1..0..1

..0..0..1..1..0..1..1....0..0..1..1..0..1..1....0..0..1..1..0..1..1

..1..1..0..1..0..1..0....1..1..0..1..0..1..0....1..1..0..1..0..1..0

..0..0..1..0..0..0..1....0..1..1..0..0..0..1....0..1..1..0..0..0..1

..1..0..1..0..1..1..0....1..0..0..0..1..1..0....1..0..0..0..1..1..0

..1..1..0..1..0..1..1....1..1..0..1..0..1..1....1..0..1..1..0..1..1

CROSSREFS

Superdiagonal 1 of A181019.

Sequence in context: A266186 A306673 A335892 * A049631 A239955 A346114

Adjacent sequences: A181017 A181018 A181019 * A181021 A181022 A181023

KEYWORD

nonn,more

AUTHOR

R. H. Hardin, Sep 30 2010

STATUS

approved