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A263054 Number of (n+1) X (2+1) 0..1 arrays with each row and column not divisible by 3, read as a binary number with top and left being the most significant bits. 1
2, 33, 142, 895, 4314, 22921, 113486, 577071, 2877562, 14455993, 72225582, 361607935, 1807659674, 9041669481, 45205690126, 226052092111, 1130241870522, 5651375017753, 28256745002222, 141284885366175, 706423516399834 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

FORMULA

Empirical: a(n) = 5*a(n-1) + 12*a(n-2) - 60*a(n-3) - 39*a(n-4) + 195*a(n-5) + 28*a(n-6) - 140*a(n-7).

Empirical g.f.: x*(2 + 23*x - 47*x^2 - 91*x^3 + 193*x^4 + 28*x^5 - 140*x^6) / ((1 - x)*(1 + x)*(1 - 2*x)*(1 + 2*x)*(1 - 5*x)*(1 - 7*x^2)). - Colin Barker, Jan 01 2019

EXAMPLE

Some solutions for n=4:

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

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

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

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

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

CROSSREFS

Column 2 of A263060.

Sequence in context: A282726 A097978 A156369 * A128152 A052403 A006558

Adjacent sequences:  A263051 A263052 A263053 * A263055 A263056 A263057

KEYWORD

nonn

AUTHOR

R. H. Hardin, Oct 08 2015

STATUS

approved

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Last modified March 20 05:34 EDT 2019. Contains 321344 sequences. (Running on oeis4.)