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A281054 Number of nX6 0..1 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards. 1
6, 251, 1403, 5400, 16875, 46610, 119205, 288527, 671451, 1515524, 3339671, 7217269, 15347530, 32196671, 66765699, 137073842, 278977066, 563443975, 1130260537, 2253558987, 4468793135, 8818038639, 17322550753, 33890757331 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 6 of A281056.

LINKS

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

FORMULA

Empirical: a(n) = 3*a(n-1) +3*a(n-2) -11*a(n-3) -9*a(n-4) +15*a(n-5) +20*a(n-6) +3*a(n-7) -18*a(n-8) -27*a(n-9) -9*a(n-10) +15*a(n-11) +20*a(n-12) +12*a(n-13) -7*a(n-15) -6*a(n-16) -3*a(n-17) -a(n-18) for n>21

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Cf. A281056.

Sequence in context: A229631 A206307 A229475 * A056238 A335158 A221822

Adjacent sequences:  A281051 A281052 A281053 * A281055 A281056 A281057

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 13 2017

STATUS

approved

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Last modified September 27 15:39 EDT 2022. Contains 357062 sequences. (Running on oeis4.)