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 A204101 Number of (n+1)X(n+1) 0..2 arrays with column and row pair sums b(i,j)=a(i,j)+a(i,j-1) and c(i,j)=a(i,j)+a(i-1,j) such that b(i,j)*b(i-1,j)-c(i,j)*c(i,j-1) is nonzero 1
 36, 864, 46656, 5738688, 1631513664, 1084257353088, 1688734588654656, 6186063092597707968, 53367767165496952526400, 1085885663438501136777646080, 52151788282239671615810458238016 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Also 0..2 arrays with no 2X2 subblock having equal diagonal elements or equal antidiagonal elements Diagonal of A204106 LINKS R. H. Hardin, Table of n, a(n) for n = 1..13 EXAMPLE Some solutions for n=5 ..2..1..2..1..1..1....0..0..0..0..0..0....2..2..1..2..2..1....2..1..0..2..1..2 ..2..0..2..0..2..2....1..2..2..2..1..1....0..0..1..0..0..0....2..1..0..2..0..0 ..2..1..2..1..1..0....0..0..0..0..0..2....1..2..2..2..1..2....2..1..0..1..1..2 ..2..1..2..0..2..2....1..1..2..1..1..1....1..0..1..0..0..2....0..1..2..2..0..0 ..2..1..2..0..1..0....2..0..0..0..2..2....2..2..1..2..1..2....2..1..0..1..1..1 ..0..1..2..0..2..2....1..1..1..1..1..0....0..0..0..0..0..2....0..1..2..2..2..0 CROSSREFS Sequence in context: A264192 A122038 A222926 * A283199 A346323 A243569 Adjacent sequences:  A204098 A204099 A204100 * A204102 A204103 A204104 KEYWORD nonn AUTHOR R. H. Hardin Jan 10 2012 STATUS approved

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Last modified January 28 17:48 EST 2022. Contains 350657 sequences. (Running on oeis4.)