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A202201 Number of (n+2) X 9 binary arrays avoiding patterns 001 and 101 in rows and columns. 1
2430, 11880, 44550, 138996, 378378, 926640, 2084940, 4375800, 8664084, 16325712, 29476980, 51279480, 86337900, 141210432, 225054126, 350430300, 534298050, 799227000, 1174863690, 1699689420, 2423110950, 3407929200, 4733235000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 7 of A202202.

LINKS

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

FORMULA

Empirical: a(n) = (n+9)*(n+8)*(n+7)*(n+6)*(n+5)*(n+4)*(n+3)*(n+2)^2/2240.

Conjectures from Colin Barker, May 27 2018: (Start)

G.f.: 18*x*(135 - 690*x + 1950*x^2 - 3528*x^3 + 4326*x^4 - 3660*x^5 + 2115*x^6 - 800*x^7 + 179*x^8 - 18*x^9) / (1 - x)^10.

a(n) = 10*a(n-1) - 45*a(n-2) + 120*a(n-3) - 210*a(n-4) + 252*a(n-5) - 210*a(n-6) + 120*a(n-7) - 45*a(n-8) + 10*a(n-9) - a(n-10) for n>10.

(End)

EXAMPLE

Some solutions for n=1:

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

..1..1..1..1..1..1..1..1..1....1..1..1..1..1..1..1..1..1

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

CROSSREFS

Cf. A202202.

Sequence in context: A156120 A078868 A186874 * A147984 A229871 A192767

Adjacent sequences:  A202198 A202199 A202200 * A202202 A202203 A202204

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 14 2011

STATUS

approved

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Last modified August 10 14:50 EDT 2020. Contains 336381 sequences. (Running on oeis4.)