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A209380 1/4 the number of (n+1)X7 0..2 arrays with every 2X2 subblock having distinct edge sums 1
128, 410, 840, 4004, 8648, 52784, 114056, 790712, 1693448, 12487208, 26563080, 201742280, 427484168, 3292956296, 6963468296, 54006743816, 114088980488, 887752094216, 1874426109960, 14608478297096, 30837161410568 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 6 of A209382

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) +38*a(n-2) -38*a(n-3) -516*a(n-4) +516*a(n-5) +3144*a(n-6) -3144*a(n-7) -8480*a(n-8) +8480*a(n-9) +7936*a(n-10) -7936*a(n-11)

EXAMPLE

Some solutions for n=4

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

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

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

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

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

CROSSREFS

Sequence in context: A220582 A203449 A195090 * A135271 A223316 A123293

Adjacent sequences:  A209377 A209378 A209379 * A209381 A209382 A209383

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 07 2012

STATUS

approved

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Last modified May 21 17:51 EDT 2022. Contains 353921 sequences. (Running on oeis4.)