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A275135
Number of 6Xn 0..2 arrays with no element equal to any value at offset (-2,-2) (-1,0) or (-1,1) and new values introduced in order 0..2.
1
16, 324, 1083, 8321, 62378, 473185, 3586068, 27224209, 206864716, 1571281413, 11942779144, 90722922402, 689405748706, 5238174766697, 39801761785044, 302425691696718, 2297924356585952, 17460451254284279, 132669830674540739
OFFSET
1,1
COMMENTS
Row 6 of A275131.
LINKS
FORMULA
Empirical: a(n) = a(n-1) +32*a(n-2) +117*a(n-3) +301*a(n-4) -196*a(n-5) -6255*a(n-6) -3361*a(n-7) -3603*a(n-8) -22745*a(n-9) +165021*a(n-10) +8504*a(n-11) -100758*a(n-12) +692296*a(n-13) -1045155*a(n-14) -356088*a(n-15) +1094300*a(n-16) -3137949*a(n-17) +2346676*a(n-18) +3048039*a(n-19) -3364817*a(n-20) +4783757*a(n-21) +1001864*a(n-22) -4054644*a(n-23) +818224*a(n-24) -774400*a(n-26) for n>28
EXAMPLE
Some solutions for n=4
..0..1..0..1. .0..0..1..2. .0..0..0..0. .0..0..1..0. .0..1..1..1
..2..2..2..0. .2..2..0..0. .1..2..1..1. .2..2..2..2. .2..2..0..0
..1..1..1..2. .1..1..2..1. .0..0..2..2. .1..0..1..1. .0..1..1..2
..0..0..0..0. .2..0..0..0. .1..1..0..0. .2..2..0..0. .2..2..0..1
..1..1..2..2. .1..1..2..2. .2..2..2..2. .1..1..2..2. .0..1..2..2
..0..0..1..1. .0..0..0..1. .0..1..0..0. .0..0..1..1. .2..0..0..1
CROSSREFS
Cf. A275131.
Sequence in context: A224768 A159536 A274893 * A276297 A229456 A246876
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jul 17 2016
STATUS
approved