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 A184100 One quarter the number of n X n toroidal 0..3 arrays with each element having the sum of its vertical neighbors equal to the sum of its horizontal neighbors 0
 1, 4, 85, 484, 3661, 28900, 137845, 1322500 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS One quarter the number of solutions in 0..3 of a 1-d velocity-one wave equation utt=uxx on a periodic grid Diagonal of A184101 LINKS EXAMPLE Some solutions for 5X5 ..2..0..3..3..0....1..2..1..1..3....2..1..1..2..1....3..1..2..1..3 ..0..2..0..3..3....2..1..2..3..0....1..0..2..2..2....2..3..2..2..1 ..3..0..2..0..3....0..2..3..1..2....0..2..1..2..2....1..3..3..2..1 ..3..3..0..2..0....2..2..1..2..1....3..1..2..1..0....2..1..3..2..2 ..0..3..3..0..2....3..1..1..1..2....1..3..1..0..2....2..2..0..3..3 CROSSREFS Sequence in context: A287248 A225164 A229185 * A059830 A189831 A223955 Adjacent sequences:  A184097 A184098 A184099 * A184101 A184102 A184103 KEYWORD nonn AUTHOR R. H. Hardin Jan 09 2011 STATUS approved

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Last modified October 25 01:18 EDT 2020. Contains 338010 sequences. (Running on oeis4.)