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A207935 Number of n X 5 0..1 arrays avoiding 0 0 1 and 1 0 0 horizontally and 0 0 1 and 1 1 0 vertically. 1
14, 196, 844, 2422, 5594, 11256, 20568, 34986, 56294, 86636, 128548, 184990, 259378, 355616, 478128, 631890, 822462, 1056020, 1339388, 1680070, 2086282, 2566984, 3131912, 3791610, 4557462, 5441724, 6457556, 7619054, 8941282, 10440304 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 5 of A207938.

LINKS

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

FORMULA

Empirical: a(n) = 6*a(n-1) - 15*a(n-2) + 20*a(n-3) - 15*a(n-4) + 6*a(n-5) - a(n-6).

Conjectures from Colin Barker, Jun 26 2018: (Start)

G.f.: 2*x*(7 + 56*x - 61*x^2 + 9*x^3 + 6*x^4 - x^5) / (1 - x)^6.

a(n) = (30 - 149*n + 10*n^2 + 250*n^3 + 65*n^4 + 4*n^5) / 15.

(End)

EXAMPLE

Some solutions for n=4:

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

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

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

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

CROSSREFS

Cf. A207938.

Sequence in context: A207943 A207388 A207516 * A208695 A207245 A208166

Adjacent sequences:  A207932 A207933 A207934 * A207936 A207937 A207938

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 21 2012

STATUS

approved

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Last modified January 22 07:31 EST 2022. Contains 350481 sequences. (Running on oeis4.)