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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

R. H. Hardin, Table of n, a(n) for n = 1..210

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

Adjacent sequences:  A218994 A218995 A218996 * A218998 A218999 A219000

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 09 2012

STATUS

approved

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Last modified August 15 17:39 EDT 2022. Contains 356148 sequences. (Running on oeis4.)