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A303625 Number of 3Xn 0..1 arrays with every element equal to 0, 2, 3, 4, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. 1
4, 2, 38, 68, 362, 1283, 5411, 22516, 96189, 417555, 1829258, 8090336, 35972626, 160686336, 719920275, 3232692431, 14538525542, 65457371351, 294941937573, 1329700498750, 5997079537476, 27054800037678, 122076548954830 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Row 3 of A303624.
LINKS
FORMULA
Empirical: a(n) = 8*a(n-1) -9*a(n-2) -54*a(n-3) +79*a(n-4) +193*a(n-5) -246*a(n-6) -383*a(n-7) +307*a(n-8) +547*a(n-9) -250*a(n-10) -458*a(n-11) +174*a(n-12) +193*a(n-13) -66*a(n-14) -34*a(n-15) -3*a(n-16) for n>17
EXAMPLE
Some solutions for n=5
..0..0..0..0..0. .0..0..1..0..1. .0..0..1..1..0. .0..1..1..1..1
..0..0..0..0..1. .0..0..1..0..1. .0..0..0..1..1. .0..1..1..1..1
..1..0..1..0..0. .1..0..0..0..0. .0..0..0..1..1. .1..1..0..1..1
CROSSREFS
Cf. A303624.
Sequence in context: A102015 A302890 A307974 * A123850 A280780 A264755
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 27 2018
STATUS
approved

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Last modified June 14 12:11 EDT 2024. Contains 373397 sequences. (Running on oeis4.)