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 A181238 Number of (4*n)X4 binary matrices with all row sums equal and all column sums equal 1
 140, 49772, 33235358, 27896484332, 26012734507190, 25785064658274014, 26631749414632177802, 28342597507242978860012, 30862541359435652055581702, 34221243248277031078812700022, 38507504930060734566868274154362 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Row 4 of A181236 LINKS R. H. Hardin, Table of n, a(n) for n=1..22 EXAMPLE Some solutions for 4X4 ..1..1..0..1....1..1..0..0....0..1..0..1....0..1..0..0....1..0..0..1 ..1..0..1..1....0..0..1..1....1..0..0..1....0..0..0..1....1..1..0..0 ..0..1..1..1....1..0..0..1....0..1..1..0....0..0..1..0....0..0..1..1 ..1..1..1..0....0..1..1..0....1..0..1..0....1..0..0..0....0..1..1..0 CROSSREFS Sequence in context: A190078 A091755 A189552 * A211420 A185402 A216729 Adjacent sequences: A181235 A181236 A181237 * A181239 A181240 A181241 KEYWORD nonn AUTHOR R. H. Hardin Oct 10 2010 STATUS approved

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Last modified June 3 03:21 EDT 2023. Contains 363103 sequences. (Running on oeis4.)