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 A220331 Equals two maps: number of 4 X n binary arrays indicating the locations of corresponding elements equal to exactly two of their horizontal and antidiagonal neighbors in a random 0..1 4 X n array. 0
 1, 37, 508, 6657, 92093, 1335202, 18836493, 265346645, 3750121527 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Row 4 of A220328. LINKS Table of n, a(n) for n=1..9. EXAMPLE Some solutions for n=3 ..0..0..1....0..1..0....0..0..0....0..0..1....0..0..1....0..1..0....0..0..1 ..1..0..1....0..1..0....0..1..1....1..0..0....1..1..0....0..1..0....0..0..0 ..0..0..1....1..0..0....0..0..0....0..1..0....0..0..1....1..1..1....0..0..0 ..1..0..0....0..0..0....0..1..0....0..1..0....0..0..0....0..1..0....1..1..0 CROSSREFS Cf. A220328. Sequence in context: A197215 A264419 A197240 * A142764 A256811 A123035 Adjacent sequences: A220328 A220329 A220330 * A220332 A220333 A220334 KEYWORD nonn AUTHOR R. H. Hardin, Dec 10 2012 STATUS approved

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Last modified November 29 06:17 EST 2023. Contains 367422 sequences. (Running on oeis4.)