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A276295
Number of nX4 0..2 arrays with no element equal to any value at offset (-2,-1) (-1,1) or (0,-1) and new values introduced in order 0..2.
1
4, 36, 173, 1017, 5965, 34865, 203933, 1192701, 6974781, 40786925, 238509373, 1394719389, 8155807421, 47692103389, 278885349565, 1630815353885, 9536385985277, 55765143107101, 326093248975229, 1906868691945053
OFFSET
1,1
COMMENTS
Column 4 of A276299.
LINKS
FORMULA
Empirical: a(n) = 9*a(n-1) -20*a(n-2) +17*a(n-3) -65*a(n-4) +116*a(n-5) -40*a(n-6) +124*a(n-7) -172*a(n-8) +16*a(n-9) -48*a(n-10) +64*a(n-11) for n>13
EXAMPLE
Some solutions for n=4
..0..1..0..2. .0..1..2..0. .0..1..0..1. .0..1..0..1. .0..1..0..2
..0..1..0..2. .2..1..2..0. .0..2..0..2. .0..2..0..2. .0..2..0..1
..2..1..0..1. .0..1..2..0. .1..2..0..2. .1..2..0..2. .0..1..0..1
..0..1..0..2. .2..0..2..1. .1..2..1..2. .0..2..0..1. .0..1..0..1
CROSSREFS
Cf. A276299.
Sequence in context: A270989 A272557 A370660 * A272146 A372218 A034569
KEYWORD
nonn
AUTHOR
R. H. Hardin, Aug 28 2016
STATUS
approved