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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 7 of A274858.

LINKS

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

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: A264093 A062261 A060624 * A274754 A008789 A207996

Adjacent sequences:  A274854 A274855 A274856 * A274858 A274859 A274860

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jul 09 2016

STATUS

approved

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Last modified October 15 15:45 EDT 2021. Contains 348033 sequences. (Running on oeis4.)