A275091 - OEIS

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A275091

Number of 3Xn 0..2 arrays with no element equal to any value at offset (0,-2) (-1,-2) or (-2,-1) and new values introduced in order 0..2.

5, 81, 192, 508, 1680, 5304, 17184, 54484, 176736, 566532, 1831420, 5898428, 19030840, 61351112, 197821048, 637917924, 2056541796, 6631985064, 21381565940, 68947715488, 222300888872, 716808527616, 2311205195976, 7452291640756

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

OFFSET

1,1

COMMENTS

Row 3 of A275090.

LINKS

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

FORMULA

Empirical: a(n) = 2*a(n-1) +9*a(n-2) -10*a(n-3) -30*a(n-4) +3*a(n-5) +90*a(n-6) +117*a(n-7) -366*a(n-8) -129*a(n-9) +477*a(n-10) -102*a(n-11) -166*a(n-12) +659*a(n-13) +144*a(n-14) -1305*a(n-15) -317*a(n-16) +1101*a(n-17) +9*a(n-18) -613*a(n-19) +657*a(n-20) -96*a(n-21) -422*a(n-22) +72*a(n-23) +167*a(n-24) +295*a(n-25) -252*a(n-26) -148*a(n-27) +133*a(n-28) +33*a(n-29) +19*a(n-30) -39*a(n-31) +8*a(n-33) +2*a(n-34) -a(n-36) for n>38

EXAMPLE

Some solutions for n=4

..0..1..1..0. .0..1..2..0. .0..0..1..2. .0..0..1..2. .0..1..2..2

..2..1..1..0. .0..1..1..0. .0..1..1..2. .2..2..1..1. .0..1..1..2

..2..1..0..0. .1..2..2..0. .2..1..1..0. .2..1..1..0. .1..2..2..0

CROSSREFS

Cf. A275090.

Sequence in context: A277302 A373855 A189443 * A275347 A110257 A370197

Adjacent sequences: A275088 A275089 A275090 * A275092 A275093 A275094

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jul 16 2016

STATUS

approved