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 A184040 1/9 the number of (n+1)X(n+1) 0..2 arrays with all 2X2 subblocks having the same four values 0
 9, 21, 41, 81, 153, 297, 569, 1113, 2169, 4281, 8441, 16761, 33273, 66297 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Diagonal of A184048 LINKS EXAMPLE Some solutions for 5X5 ..1..0..1..0..1....1..2..1..0..1....1..0..1..0..1....0..1..0..1..0 ..1..0..1..0..1....0..0..0..2..0....2..0..2..0..2....1..1..1..1..1 ..0..1..0..1..0....1..2..1..0..1....0..1..0..1..0....1..0..1..0..1 ..0..1..0..1..0....0..0..0..2..0....0..2..0..2..0....1..1..1..1..1 ..0..1..0..1..0....1..2..1..0..1....1..0..1..0..1....0..1..0..1..0 CROSSREFS Sequence in context: A036704 A107890 A110209 * A242990 A053476 A110680 Adjacent sequences:  A184037 A184038 A184039 * A184041 A184042 A184043 KEYWORD nonn AUTHOR R. H. Hardin Jan 08 2011 STATUS approved

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Last modified December 5 21:00 EST 2019. Contains 329779 sequences. (Running on oeis4.)