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A280808 Number of nX6 0..1 arrays with no element equal to more than two of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards. 1
0, 284, 6540, 37644, 155560, 547197, 1736603, 5150299, 14554327, 39708623, 105469880, 274358836, 702041419, 1772651619, 4426877398, 10952897674, 26883495456, 65525790275, 158732212994, 382416259916, 916790487361 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 6 of A280810.

LINKS

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

FORMULA

Empirical: a(n) = 13*a(n-1) -72*a(n-2) +220*a(n-3) -400*a(n-4) +432*a(n-5) -256*a(n-6) +70*a(n-7) -54*a(n-8) +183*a(n-9) -249*a(n-10) -51*a(n-11) +573*a(n-12) -672*a(n-13) +249*a(n-14) +135*a(n-15) -204*a(n-16) +12*a(n-17) +225*a(n-18) -57*a(n-19) -390*a(n-20) +422*a(n-21) -107*a(n-22) -63*a(n-23) +138*a(n-24) -144*a(n-25) +33*a(n-27) +78*a(n-28) -54*a(n-29) -13*a(n-30) -17*a(n-31) -12*a(n-32) +70*a(n-33) -31*a(n-34) -12*a(n-35) +3*a(n-36) -6*a(n-37) +15*a(n-38) -3*a(n-39) -3*a(n-40) -a(n-42) +a(n-43) for n>53

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Cf. A280810.

Sequence in context: A108110 A218400 A196893 * A285892 A049024 A277771

Adjacent sequences:  A280805 A280806 A280807 * A280809 A280810 A280811

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 08 2017

STATUS

approved

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Last modified November 17 08:39 EST 2019. Contains 329217 sequences. (Running on oeis4.)