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 A243721 Number of length n+2 0..n arrays with no three unequal elements in a row and no three equal elements in a row and new values 0..n introduced in 0..n order 1
 3, 6, 12, 25, 53, 116, 259, 594, 1389, 3323, 8095, 20113, 50814, 130632, 341034, 904331, 2432412, 6636112, 18345413, 51381635, 145691912, 418131443, 1213928928, 3564262737, 10579009345, 31733010233, 96162631881, 294324273852 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Diagonal of A243729 LINKS R. H. Hardin, Table of n, a(n) for n = 1..209 EXAMPLE Some solutions for n=6 ..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0 ..1....1....1....0....0....1....0....1....0....0....1....1....1....1....0....1 ..1....0....1....1....1....0....1....1....1....1....0....0....0....0....1....0 ..2....0....2....1....0....1....0....2....0....0....0....0....1....0....0....0 ..1....2....1....2....0....1....1....2....0....1....2....1....1....2....0....2 ..2....2....1....2....2....0....0....0....1....1....2....0....2....2....2....0 ..2....0....0....0....0....1....0....0....0....0....3....1....1....0....2....0 ..1....0....0....2....0....0....2....2....1....0....2....1....2....2....3....3 CROSSREFS Sequence in context: A243726 A243727 A243728 * A280109 A099445 A004067 Adjacent sequences: A243718 A243719 A243720 * A243722 A243723 A243724 KEYWORD nonn AUTHOR R. H. Hardin, Jun 09 2014 STATUS approved

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Last modified December 2 09:21 EST 2023. Contains 367516 sequences. (Running on oeis4.)