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A188841 Number of n X 7 binary arrays without the pattern 0 1 diagonally or vertically. 1
128, 987, 3280, 7753, 15504, 28101, 47652, 76912, 119416, 179630, 263120, 376740, 528840, 729495, 990756, 1326924, 1754848, 2294248, 2968064, 3802832, 4829088, 6081801, 7600836, 9431448, 11624808, 14238562, 17337424, 20993804, 25288472 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 7 of A188843.

LINKS

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

FORMULA

Empirical: a(n) = (1/5040)*n^7 + (1/72)*n^6 + (143/360)*n^5 + (53/9)*n^4 + (33667/720)*n^3 + (12679/72)*n^2 + (9439/70)*n - 572 for n>4.

Empirical g.f.: x*(128 - 37*x - 1032*x^2 + 1981*x^3 - 992*x^4 - 605*x^5 + 700*x^6 - 58*x^7 - 96*x^8 + 3*x^9 + 8*x^10 + x^11) / (1 - x)^8. - Colin Barker, May 01 2018

EXAMPLE

Some solutions for 3 X 7:

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

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

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

CROSSREFS

Cf. A188843.

Sequence in context: A188151 A297643 A224043 * A188704 A297344 A183976

Adjacent sequences:  A188838 A188839 A188840 * A188842 A188843 A188844

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 12 2011

STATUS

approved

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Last modified February 28 22:44 EST 2020. Contains 332336 sequences. (Running on oeis4.)