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 A251309 Number of (n+1)X(n+1) 0..1 arrays with no 2X2 subblock having the maximum of its diagonal elements greater than the absolute difference of its antidiagonal elements 1
 10, 79, 890, 16006, 451826, 20080487, 1401489913, 153420339471, 26520184876394, 7212082506701341, 3095565630909130451, 2090970229906057682594, 2228353475131985328672710, 3744199174821109524081657694 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Diagonal of A251317 LINKS R. H. Hardin, Table of n, a(n) for n = 1..19 EXAMPLE Some solutions for n=4 ..1..1..0..0..1....1..1..0..0..0....1..1..0..0..0....1..0..0..0..1 ..0..1..0..0..0....0..1..1..1..0....0..1..1..0..0....1..1..1..0..1 ..0..1..0..0..0....0..0..0..1..0....1..0..1..1..0....0..0..1..1..0 ..0..1..1..1..1....0..0..0..1..1....1..0..0..1..0....0..0..0..1..1 ..1..0..0..0..1....1..0..0..0..0....1..0..0..1..0....1..1..0..0..1 CROSSREFS Sequence in context: A006329 A077245 A036732 * A206764 A253649 A244729 Adjacent sequences:  A251306 A251307 A251308 * A251310 A251311 A251312 KEYWORD nonn AUTHOR R. H. Hardin, Dec 01 2014 STATUS approved

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Last modified December 15 20:00 EST 2019. Contains 330000 sequences. (Running on oeis4.)