A181021 - OEIS

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A181021

Maximum number of 1s in an nX(n+2) binary matrix with no three 1s adjacent in a line along a row, column or diagonally.

2, 6, 9, 13, 20, 26, 33, 42, 52, 62

(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 6X8

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

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

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

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

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

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

CROSSREFS

Superdiagonal 2 of A181019.

Sequence in context: A372061 A094111 A351712 * A048162 A226823 A171866

Adjacent sequences: A181018 A181019 A181020 * A181022 A181023 A181024

KEYWORD

nonn,more

AUTHOR

R. H. Hardin, Sep 30 2010

STATUS

approved