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A238720 Number of nX2 0..2 arrays with no element equal to the sum modulo 3 of elements to its left or elements above it 1
2, 4, 10, 16, 42, 64, 170, 256, 682, 1024, 2730, 4096, 10922, 16384, 43690, 65536, 174762, 262144, 699050, 1048576, 2796202, 4194304, 11184810, 16777216, 44739242, 67108864, 178956970, 268435456, 715827882, 1073741824, 2863311530, 4294967296 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 2 of A238726

LINKS

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

FORMULA

Empirical: a(n) = 5*a(n-2) -4*a(n-4)

EXAMPLE

Some solutions for n=5

..2..1....2..1....2..1....1..2....2..1....1..2....1..2....1..2....1..2....1..2

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

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

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

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

CROSSREFS

Sequence in context: A050871 A348305 A277918 * A264585 A077635 A125754

Adjacent sequences:  A238717 A238718 A238719 * A238721 A238722 A238723

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 03 2014

STATUS

approved

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Last modified September 25 18:27 EDT 2022. Contains 356986 sequences. (Running on oeis4.)