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A202333 Number of (n+1) X 7 binary arrays with consecutive windows of two bits considered as a binary number nondecreasing in every row and column. 1
81, 270, 746, 1796, 3896, 7790, 14588, 25885, 43903, 71658, 113154, 173606, 259694, 379850, 544580, 766823, 1062349, 1450198, 1953162, 2598312, 3417572, 4448342, 5734172, 7325489, 9280379, 11665426, 14556610, 18040266, 22214106, 27188306 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 6 of A202335.

LINKS

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

FORMULA

Empirical: a(n) = (1/2520)*n^7 + (11/720)*n^6 + (167/720)*n^5 + (265/144)*n^4 + (5999/720)*n^3 + (974/45)*n^2 + (4191/140)*n + 19.

Conjectures from Colin Barker, May 28 2018: (Start)

G.f.: x*(81 - 378*x + 854*x^2 - 1148*x^3 + 966*x^4 - 502*x^5 + 148*x^6 - 19*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=5:

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

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

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

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

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

CROSSREFS

Cf. A202335.

Sequence in context: A237234 A237227 A206094 * A207042 A206087 A236809

Adjacent sequences:  A202330 A202331 A202332 * A202334 A202335 A202336

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 17 2011

STATUS

approved

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Last modified December 3 05:05 EST 2021. Contains 349445 sequences. (Running on oeis4.)