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A219411 Unmatched value maps: number of 2 X n binary arrays indicating the locations of corresponding elements not equal to any horizontal or antidiagonal neighbor in a random 0..2 2 X n array. 1
1, 7, 28, 98, 351, 1261, 4523, 16233, 58268, 209132, 750597, 2693993, 9669101, 34703683, 124556124, 447048462, 1604516243, 5758821685, 20669175143, 74184412085, 266257698140, 955634207080, 3429897967721, 12310358902801 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Row 2 of A219410.

LINKS

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

FORMULA

Empirical: a(n) = 4*a(n-1) - 3*a(n-2) + 6*a(n-3) - 3*a(n-4) + 4*a(n-5).

Empirical g.f.: x*(1 + 3*x + 3*x^2 + x^3 + 4*x^4) / ((1 - x + x^2)*(1 - 3*x - x^2 - 4*x^3)). - Colin Barker, Jul 26 2018

EXAMPLE

Some solutions for n=3:

..0..0..1....0..0..1....0..0..0....0..0..0....0..0..0....1..0..0....1..1..1

..1..1..1....1..0..0....0..0..0....1..0..0....1..0..1....0..0..1....1..0..0

CROSSREFS

Cf. A219410.

Sequence in context: A022572 A193654 A241400 * A224404 A331197 A024207

Adjacent sequences:  A219408 A219409 A219410 * A219412 A219413 A219414

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 19 2012

STATUS

approved

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Last modified May 18 23:31 EDT 2022. Contains 353826 sequences. (Running on oeis4.)