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A231109 Number of 3Xn 0..3 arrays x(i,j) with each element horizontally or antidiagonally next to at least one element with value (x(i,j)+1) mod 4, no adjacent elements equal, and upper left element zero 1
0, 0, 8, 48, 286, 1748, 10734, 65934, 404984, 2487534, 15279170, 93849326, 576451382, 3540741892, 21748327444, 133584927368, 820519778376, 5039885260498, 30956527928058, 190144531428150, 1167926290556226 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Row 3 of A231108

LINKS

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

FORMULA

Empirical: a(n) = 10*a(n-1) -26*a(n-2) +6*a(n-3) +60*a(n-4) -56*a(n-5) -38*a(n-6) +54*a(n-7) -9*a(n-8) +18*a(n-9) -20*a(n-10) +2*a(n-12) for n>16

EXAMPLE

Some solutions for n=4

..0..1..0..1....0..1..2..1....0..1..2..3....0..1..0..3....0..1..2..0

..2..3..2..1....0..3..2..1....0..1..0..1....2..3..2..3....0..3..1..2

..2..3..0..3....2..3..0..3....0..3..2..1....0..1..0..3....2..0..3..2

CROSSREFS

Sequence in context: A295047 A295375 A081554 * A079743 A079765 A079744

Adjacent sequences:  A231106 A231107 A231108 * A231110 A231111 A231112

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 03 2013

STATUS

approved

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Last modified June 12 09:24 EDT 2021. Contains 344946 sequences. (Running on oeis4.)