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A281203 Number of n X 6 0..1 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards. 1
10, 94, 310, 804, 1906, 4248, 9118, 19026, 38916, 78356, 155834, 306840, 599204, 1162074, 2240438, 4297644, 8207494, 15613762, 29601530, 55948952, 105457480, 198283598, 371980528, 696408816, 1301351164, 2427600480, 4521378510 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

FORMULA

Empirical: a(n) = 2*a(n-1) + 3*a(n-2) - 4*a(n-3) - 6*a(n-4) + 4*a(n-6) + 6*a(n-7) + 3*a(n-8) - 2*a(n-9) - 3*a(n-10) - 2*a(n-11) - a(n-12).

Empirical g.f.: 2*x*(1 + x)*(5 + 32*x + 14*x^2 - 43*x^3 - 55*x^4 - 31*x^5 + x^6 + 28*x^7 + 24*x^8 + 10*x^9 + 3*x^10) / (1 - x - 2*x^2 + x^4 + x^5 + x^6)^2. - Colin Barker, Feb 17 2019

EXAMPLE

Some solutions for n=4:

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

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

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

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

CROSSREFS

Column 6 of A281205.

Sequence in context: A192902 A192903 A050793 * A126633 A125422 A190988

Adjacent sequences:  A281200 A281201 A281202 * A281204 A281205 A281206

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 17 2017

STATUS

approved

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Last modified March 19 17:21 EDT 2019. Contains 321330 sequences. (Running on oeis4.)