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A209548 1/4 the number of (n+1)X4 0..3 arrays with every 2X2 subblock having exactly two distinct clockwise edge differences 1
61, 562, 5075, 46515, 425803, 3901194, 35741496, 327471411, 3000373035, 27490276714, 251873944521, 2307743577771, 21144231048767, 193729722925588, 1775009260945536, 16263162106133544, 149007922275551448 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A209553

LINKS

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

FORMULA

Empirical: a(n) = 15*a(n-1) -59*a(n-2) +27*a(n-3) +267*a(n-4) -488*a(n-5) +111*a(n-6) +312*a(n-7) -174*a(n-8) -30*a(n-9) +18*a(n-10) +2*a(n-11)

EXAMPLE

Some solutions for n=4

..1..0..3..0....1..0..3..0....1..2..1..2....3..2..3..0....3..1..3..1

..0..1..2..1....2..3..0..3....0..3..2..3....2..3..2..1....1..3..1..3

..3..2..1..2....1..2..1..2....3..0..1..0....1..0..1..2....3..1..3..1

..0..1..0..3....2..1..0..3....2..1..2..1....0..1..2..1....1..3..1..3

..1..0..1..2....1..2..3..0....3..0..1..0....3..2..3..2....3..1..3..1

CROSSREFS

Sequence in context: A302531 A061002 A303412 * A302898 A234926 A069595

Adjacent sequences:  A209545 A209546 A209547 * A209549 A209550 A209551

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 10 2012

STATUS

approved

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Last modified December 2 03:43 EST 2021. Contains 349437 sequences. (Running on oeis4.)