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A205739 Number of 4X(n+1) 0..2 arrays with every 2 X 2 subblock having the same number of clockwise edge increases as its horizontal neighbors and no 2 X 2 subblock having the same number of counterclockwise edge increases as its vertical neighbors. 1
1683, 3318, 14715, 80088, 450339, 2565900, 14781282, 85852548, 502097979, 2953275825, 17454550770, 103577971653, 616733949822, 3682641041940, 22041854965854, 132187997823285, 794047508972499, 4776288839441496 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 3 of A205736.

LINKS

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

FORMULA

Empirical: a(n) = 23*a(n-1) -207*a(n-2) +867*a(n-3) -1178*a(n-4) -3567*a(n-5) +15272*a(n-6) -12652*a(n-7) -30210*a(n-8) +69591*a(n-9) -24010*a(n-10) -68468*a(n-11) +85661*a(n-12) -25742*a(n-13) -16279*a(n-14) +13561*a(n-15) -2008*a(n-16) -1025*a(n-17) +416*a(n-18) -44*a(n-19) for n>23.

EXAMPLE

Some solutions for n=4:

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

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

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

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

CROSSREFS

Sequence in context: A035766 A107562 A031539 * A031719 A206671 A205515

Adjacent sequences:  A205736 A205737 A205738 * A205740 A205741 A205742

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 30 2012

STATUS

approved

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Last modified October 27 06:31 EDT 2021. Contains 348271 sequences. (Running on oeis4.)