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A205048 Number of (n+1)X2 0..2 arrays with the number of rightwards and downwards edge increases in each 2X2 subblock equal to the number in all its horizontal and vertical neighbors 1
81, 243, 803, 2892, 10948, 43261, 174282, 709813, 2904299, 11912535, 48917149, 200991165, 826074359, 3395693794, 13959599701, 57390029458, 235944613954, 970038942121, 3988147567016, 16396640414068, 67412338625033 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 1 of A205055

LINKS

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

FORMULA

Empirical: a(n) = 8*a(n-1) -19*a(n-2) +5*a(n-3) +55*a(n-4) -130*a(n-5) +110*a(n-6) +76*a(n-7) -206*a(n-8) +143*a(n-9) -127*a(n-10) +149*a(n-11) -69*a(n-12) +26*a(n-13) -34*a(n-14) +18*a(n-15) -7*a(n-16) -3*a(n-17) +10*a(n-18) -4*a(n-19) for n>21

EXAMPLE

Some solutions for n=4

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

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

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

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

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

CROSSREFS

Sequence in context: A205055 A335843 A255625 * A008876 A031456 A045009

Adjacent sequences:  A205045 A205046 A205047 * A205049 A205050 A205051

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 21 2012

STATUS

approved

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Last modified December 7 06:50 EST 2021. Contains 349567 sequences. (Running on oeis4.)