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A202458 Number of (n+2) X 7 binary arrays with consecutive windows of three bits considered as a binary number nondecreasing in every row and column. 1
1728, 4137, 9338, 19614, 38478, 71088, 124740, 209445, 338596, 529731, 805398, 1194128, 1731522, 2461458, 3437424, 4723983, 6398376, 8552269, 11293650, 14748882, 19064918, 24411684, 30984636, 39007497, 48735180, 60456903, 74499502 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 5 of A202461.

LINKS

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

FORMULA

Empirical: a(n) = (1/840)*n^7 + (3/40)*n^6 + (47/30)*n^5 + 16*n^4 + (10847/120)*n^3 + (11557/40)*n^2 + (258737/420)*n + 715.

Conjectures from Colin Barker, May 31 2018: (Start)

G.f.: x*(1728 - 9687*x + 24626*x^2 - 36022*x^3 + 32318*x^4 - 17650*x^5 + 5408*x^6 - 715*x^7) / (1 - x)^8.

a(n) = 8*a(n-1) - 28*a(n-2) + 56*a(n-3) - 70*a(n-4) + 56*a(n-5) - 28*a(n-6) + 8*a(n-7) - a(n-8) for n>8.

(End)

EXAMPLE

Some solutions for n=4:

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

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

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

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

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

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

CROSSREFS

Cf. A202461.

Sequence in context: A305494 A032354 A305475 * A179694 A202200 A251188

Adjacent sequences:  A202455 A202456 A202457 * A202459 A202460 A202461

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 19 2011

STATUS

approved

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Last modified July 17 17:07 EDT 2018. Contains 312721 sequences. (Running on oeis4.)