A275353 Number of 3Xn 0..2 arrays with no element equal to any value at offset (-2,-1) (-2,1) or (-1,-2) and new values introduced in order 0..2.

5, 54, 288, 1536, 8192, 43712, 235072, 1264832, 6809856, 36666496, 197447168, 1063304448, 5726352128, 30839264512, 166086172928, 894467665408, 4817222467584, 25943536156672, 139721052861440, 752479440667648

Offset

1,1

Comments

Row 3 of A275352.

Links

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

Formula

Empirical: a(n) = 6*a(n-1) -2*a(n-2) -8*a(n-3) +20*a(n-4) -44*a(n-5) -160*a(n-6) -180*a(n-7) +152*a(n-8) -880*a(n-9) -928*a(n-10) +848*a(n-11) +816*a(n-12) +2752*a(n-13) +2880*a(n-14) +2560*a(n-15) -2048*a(n-16) -4096*a(n-18) for n>20

Example

Some solutions for n=4
..0..0..0..0. .0..0..0..0. .0..1..0..1. .0..1..0..1. .0..1..0..1
..1..2..1..1. .1..0..1..2. .1..0..2..0. .0..0..1..0. .0..2..1..2
..2..2..2..1. .1..2..2..1. .2..2..0..1. .0..2..2..2. .0..2..2..1

Crossrefs

Cf. A275352.

Sequence in context: A275396 A275261 A208429 * A221544 A268882 A229298

Adjacent sequences: A275350 A275351 A275352 * A275354 A275355 A275356

Keyword

nonn

Author

R. H. Hardin, Jul 24 2016

Status

approved