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A184681 Number of (n+1) X 5 binary arrays with every 2 X 2 subblock singular. 1
208, 2384, 21968, 221968, 2171152, 21547024, 212829840, 2107074576, 20846869136, 206331811088, 2041995275664, 20210243538448, 200025118846608, 1979715148636944, 19593894295270288, 193927696142858256 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A184686.

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..200

FORMULA

Empirical: a(n) = 16*a(n-1) - 51*a(n-2) - 190*a(n-3) + 1058*a(n-4) - 848*a(n-5) - 1392*a(n-6) + 1536*a(n-7).

Empirical g.f.: 16*x*(13 - 59*x - 348*x^2 + 1974*x^3 - 1692*x^4 - 2688*x^5 + 3072*x^6) / (1 - 16*x + 51*x^2 + 190*x^3 - 1058*x^4 + 848*x^5 + 1392*x^6 - 1536*x^7). - Colin Barker, Apr 14 2018

EXAMPLE

Some solutions for 3 X 5:

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

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

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

CROSSREFS

Cf. A184686

Sequence in context: A233659 A230934 A236272 * A235674 A235444 A255074

Adjacent sequences:  A184678 A184679 A184680 * A184682 A184683 A184684

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 19 2011

STATUS

approved

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Last modified August 5 13:12 EDT 2021. Contains 346469 sequences. (Running on oeis4.)