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A274753
Number of 6Xn 0..2 arrays with no element equal to any value at offset (-1,-2) (0,-1) or (-1,0) and new values introduced in order 0..2.
1
16, 243, 2584, 30349, 355504, 4190533, 49475642, 584676706, 6910844226, 81707047512, 965986300341, 11421440282793, 135038015584259, 1596629353977271, 18877567144827169, 223198901191401063
OFFSET
1,1
COMMENTS
Row 6 of A274749.
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) +152*a(n-2) +126*a(n-3) -6741*a(n-4) -9730*a(n-5) +144236*a(n-6) +211544*a(n-7) -1827425*a(n-8) -2254882*a(n-9) +15047732*a(n-10) +13461608*a(n-11) -83672422*a(n-12) -46079542*a(n-13) +318146254*a(n-14) +83743568*a(n-15) -832325842*a(n-16) -43299570*a(n-17) +1510818060*a(n-18) -133037018*a(n-19) -1921914874*a(n-20) +326729576*a(n-21) +1726512331*a(n-22) -355689576*a(n-23) -1096976553*a(n-24) +226215282*a(n-25) +489155842*a(n-26) -88109294*a(n-27) -149920421*a(n-28) +20717362*a(n-29) +30372727*a(n-30) -2785542*a(n-31) -3809133*a(n-32) +191694*a(n-33) +263142*a(n-34) -5112*a(n-35) -7560*a(n-36) for n>38
EXAMPLE
Some solutions for n=4
..0..1..2..1. .0..1..2..1. .0..1..0..1. .0..1..0..1. .0..1..2..0
..1..0..1..0. .1..0..1..0. .1..0..2..0. .1..0..1..2. .1..0..1..2
..0..1..0..1. .2..1..0..2. .0..1..0..1. .2..1..0..1. .0..2..0..1
..2..0..2..0. .1..2..1..0. .1..2..1..2. .1..0..1..0. .1..0..2..0
..0..2..0..1. .0..1..0..1. .2..0..2..1. .0..2..0..2. .0..2..0..1
..1..0..2..0. .2..0..2..0. .1..2..0..2. .2..1..2..1. .2..1..2..0
CROSSREFS
Cf. A274749.
Sequence in context: A064232 A074153 A119933 * A207995 A008788 A360759
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jul 04 2016
STATUS
approved