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A205239 Number of (n+1)X2 0..2 arrays with the number of rightwards and downwards edge increases in each 2X2 subblock differing from the number in each of its horizontal and vertical neighbors 1
81, 486, 2990, 18148, 111041, 677732, 4143102, 25302238, 154597952, 944323666, 5769147079, 35241970176, 215294819906, 1315202262082, 8034520991634, 49082022117918, 299838801088734, 1831687968517910, 11189641429502614 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 1 of A205246

LINKS

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

FORMULA

Empirical: a(n) = 27*a(n-2) +48*a(n-3) +35*a(n-4) +258*a(n-5) +400*a(n-6) +502*a(n-7) +1956*a(n-8) +2498*a(n-9) +333*a(n-10) +544*a(n-11) +2005*a(n-12) +980*a(n-13) -5963*a(n-14) -556*a(n-15) +1856*a(n-16) +2430*a(n-17) -2045*a(n-18) -2184*a(n-19) -4376*a(n-20) -1720*a(n-21) -448*a(n-22) -64*a(n-23) for n>24

EXAMPLE

Some solutions for n=4

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

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

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

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

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

CROSSREFS

Sequence in context: A237077 A236646 A205246 * A236427 A235842 A235838

Adjacent sequences:  A205236 A205237 A205238 * A205240 A205241 A205242

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 24 2012

STATUS

approved

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Last modified October 28 03:12 EDT 2021. Contains 348308 sequences. (Running on oeis4.)