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 A251142 Number of (n+1) X (n+1) 0..2 arrays with every 2 X 2 subblock summing to 4 and no 2 X 2 subblock having exactly two nonzero entries. 0
 13, 49, 143, 401, 1061, 2763, 7101, 18193, 46575, 119441, 307045, 791499, 2045725 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Diagonal of A251149. LINKS EXAMPLE Some solutions for n=4: ..1..0..1..1..1....1..1..1..1..1....0..1..0..2..1....1..1..0..1..1 ..2..1..2..0..2....1..1..1..1..1....1..2..1..1..0....1..1..2..1..1 ..1..0..1..1..1....0..2..0..2..0....0..1..0..2..1....2..0..1..0..2 ..1..2..1..1..1....1..1..1..1..1....1..2..1..1..0....1..1..2..1..1 ..0..1..0..2..0....1..1..1..1..1....1..0..1..1..2....1..1..0..1..1 CROSSREFS Cf. A251149. Sequence in context: A158480 A009951 A274974 * A319086 A146287 A289999 Adjacent sequences:  A251139 A251140 A251141 * A251143 A251144 A251145 KEYWORD nonn AUTHOR R. H. Hardin, Nov 30 2014 STATUS approved

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Last modified December 16 17:02 EST 2018. Contains 318172 sequences. (Running on oeis4.)