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A204191 Number of n X n 0..1 arrays with no occurrence of three equal elements in a row horizontally, vertically or nw-to-se diagonally, and new values 0..1 introduced in row major order. 1
1, 8, 33, 265, 3716, 85681, 3162172, 193490711, 19420814056, 3186206928387, 862553899224504, 384159816761460081, 280924309017824796979, 338777671702533919423933, 672692693382038110389392230 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Diagonal of A204197.

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..17

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Sequence in context: A005398 A240044 A069509 * A041118 A308879 A297904

Adjacent sequences:  A204188 A204189 A204190 * A204192 A204193 A204194

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 12 2012

STATUS

approved

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Last modified December 4 08:54 EST 2020. Contains 338921 sequences. (Running on oeis4.)