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A181239 Number of n X 4 binary matrices with no 2 X 2 circuit having pattern 0101 in any orientation. 1
16, 178, 2066, 23858, 275690, 3185462, 36806846, 425288998, 4914052362, 56780001474, 656071271338, 7580653428086, 87591560417790, 1012087088416198, 11694280472399626, 135122952690874754, 1561294205914890890 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A181245.

LINKS

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

FORMULA

Empirical: a(n) = 10*a(n-1) + 20*a(n-2) - 21*a(n-3) - 30*a(n-4) + 8*a(n-5).

Empirical g.f.: 2*x*(8 + 9*x - 17*x^2 - 13*x^3 + 4*x^4) / (1 - 10*x - 20*x^2 + 21*x^3 + 30*x^4 - 8*x^5). - Colin Barker, Mar 26 2018

CROSSREFS

Cf. A181245.

Sequence in context: A264297 A002399 A255255 * A021084 A227557 A269202

Adjacent sequences:  A181236 A181237 A181238 * A181240 A181241 A181242

KEYWORD

nonn

AUTHOR

R. H. Hardin, Oct 10 2010

STATUS

approved

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Last modified October 17 17:21 EDT 2021. Contains 348065 sequences. (Running on oeis4.)