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A188820 Number of n X 5 binary arrays without the pattern 0 1 diagonally or antidiagonally. 1
32, 169, 432, 841, 1360, 2025, 2800, 3721, 4752, 5929, 7216, 8649, 10192, 11881, 13680, 15625, 17680, 19881, 22192, 24649, 27216, 29929, 32752, 35721, 38800, 42025, 45360, 48841, 52432, 56169, 60016, 64009, 68112, 72361, 76720, 81225, 85840, 90601 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 5 of A188824.

LINKS

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

FORMULA

Empirical: a(n) = 2*a(n-1) - 2*a(n-3) + a(n-4) for n>5.

Conjectures from Colin Barker, Apr 29 2018: (Start)

G.f.: x*(32 + 105*x + 94*x^2 + 41*x^3 - 16*x^4) / ((1 - x)^3*(1 + x)).

a(n) = 9 - 48*n + 64*n^2 for n even.

a(n) = -48*n + 64*n^2 for n>1 and odd.

(End)

EXAMPLE

Some solutions for 3 X 5:

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

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

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

CROSSREFS

Cf. A188824.

Sequence in context: A302621 A302413 A303180 * A181209 A231299 A029534

Adjacent sequences:  A188817 A188818 A188819 * A188821 A188822 A188823

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 11 2011

STATUS

approved

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Last modified February 18 20:25 EST 2019. Contains 320262 sequences. (Running on oeis4.)