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A274857
Number of nX7 0..2 arrays with no element equal to any value at offset (-1,0) (0,-1) or (-2,-2) and new values introduced in order 0..2.
1
32, 729, 542, 2585, 12102, 58775, 289494, 1426688, 7031552, 34766640, 172447382, 856198165, 4249077675, 21078145330, 104568950459, 518896515145, 2575174869347, 12779650282427, 63417621140877, 314701428995532
OFFSET
1,1
COMMENTS
Column 7 of A274858.
LINKS
FORMULA
Empirical: a(n) = 21*a(n-1) -209*a(n-2) +1330*a(n-3) -6059*a(n-4) +20839*a(n-5) -55739*a(n-6) +118287*a(n-7) -202495*a(n-8) +284119*a(n-9) -331806*a(n-10) +326718*a(n-11) -273224*a(n-12) +193798*a(n-13) -115270*a(n-14) +56258*a(n-15) -21837*a(n-16) +6481*a(n-17) -1404*a(n-18) +210*a(n-19) -20*a(n-20) +a(n-21) for n>24
EXAMPLE
Some solutions for n=4
..0..1..2..0..1..0..1. .0..1..0..1..2..0..1. .0..1..0..2..1..2..1
..1..2..0..1..0..1..2. .2..0..1..2..0..1..2. .1..0..2..0..2..1..0
..2..0..2..0..1..2..0. .0..1..2..0..1..2..0. .0..2..1..2..1..0..2
..1..2..0..1..2..0..1. .1..2..0..2..0..1..2. .1..0..2..1..0..2..1
CROSSREFS
Cf. A274858.
Sequence in context: A062261 A060624 A351384 * A274754 A008789 A207996
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jul 09 2016
STATUS
approved