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A207458 Number of 7 X n 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 1 and 1 0 1 vertically. 1
14, 196, 546, 3850, 14896, 84266, 370734, 1922564, 8935850, 44655394, 212625504, 1045480786, 5031607126, 24563900900, 118782802866, 578049254426, 2801168057744, 13612500276634, 66026807997150, 320661548440324 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 7 of A207453.

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) + 19*a(n-2) + 6*a(n-3) - 36*a(n-4).

Empirical g.f.: 14*x*(1 + 13*x + 6*x^2 - 36*x^3) / ((1 + 2*x - 4*x^2)*(1 - 3*x - 9*x^2)). - Colin Barker, Jun 23 2018

EXAMPLE

Some solutions for n=5:

  0 1 0 1 0     1 0 1 1 0     1 1 0 1 0     1 1 0 1 1

  0 1 1 1 0     0 1 0 1 0     0 1 0 1 1     1 0 1 0 1

  0 1 0 1 0     0 1 0 1 0     0 1 0 1 1     1 0 1 0 1

  0 1 0 1 0     0 1 0 1 0     0 1 0 1 1     1 0 1 0 0

  0 1 0 1 0     0 1 0 1 0     0 1 0 1 1     1 0 1 0 0

  0 1 0 1 0     0 1 0 1 0     0 1 0 1 1     1 0 1 0 0

  0 1 0 1 0     0 1 0 1 0     0 1 0 1 1     1 0 1 0 0

CROSSREFS

Cf. A207453.

Sequence in context: A207604 A207030 A207175 * A208004 A207566 A207561

Adjacent sequences:  A207455 A207456 A207457 * A207459 A207460 A207461

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 17 2012

STATUS

approved

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Last modified May 18 18:42 EDT 2022. Contains 353824 sequences. (Running on oeis4.)