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A218997 Unmatched value maps: number of n X 3 binary arrays indicating the locations of corresponding elements not equal to any horizontal, diagonal or antidiagonal neighbor in a random 0..2 n X 3 array. 1
4, 46, 328, 2374, 17776, 131548, 973492, 7213582, 53429692, 395740366, 2931304708, 21712231084, 160822807612, 1191219388318, 8823392421952, 65355090312238, 484086844724824, 3585643697043796, 26558954938197124, 196722861904335358 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Column 3 of A219002.
LINKS
FORMULA
Empirical: a(n) = 4*a(n-1) + 15*a(n-2) + 66*a(n-3) + 63*a(n-4) + 72*a(n-5).
Empirical g.f.: 2*x*(2 + 15*x + 42*x^2 + 54*x^3 + 36*x^4) / (1 - 4*x - 15*x^2 - 66*x^3 - 63*x^4 - 72*x^5). - Colin Barker, Jul 24 2018
EXAMPLE
Some solutions for n=3:
..0..1..0....1..1..1....0..1..0....1..0..0....0..0..0....0..1..1....0..0..0
..0..0..1....0..1..0....0..0..0....0..0..1....0..1..1....1..0..0....1..0..1
..1..0..0....1..0..1....0..1..0....1..0..1....1..0..0....0..1..0....0..1..0
CROSSREFS
Cf. A219002.
Sequence in context: A119046 A273776 A131540 * A279523 A194488 A132932
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 09 2012
STATUS
approved

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Last modified March 28 04:13 EDT 2024. Contains 371235 sequences. (Running on oeis4.)