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A234770 Number of (n+1) X (1+1) 0..4 arrays with 2 X 2 edge jumps all no more than +1 in one of the clockwise or counterclockwise directions but not both. 1
88, 454, 2056, 10076, 46804, 226072, 1060636, 5086576, 23991808, 114597900, 542168944, 2583725396, 12245147680, 58277217168, 276473917972, 1314790543248, 6241143226396, 29667097057792, 140873066386336, 669466007785964 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) + 21*a(n-2) - a(n-3) - 67*a(n-4) - 10*a(n-5) + 46*a(n-6).

Empirical g.f.: 2*x*(44 + 183*x - 123*x^2 - 713*x^3 - 49*x^4 + 513*x^5) / (1 - x - 21*x^2 + x^3 + 67*x^4 + 10*x^5 - 46*x^6). - Colin Barker, Oct 16 2018

EXAMPLE

Some solutions for n=5:

..1..3....1..2....1..1....1..3....2..0....4..4....4..4....2..2....3..2....0..2

..2..2....1..0....2..3....2..3....2..1....2..3....3..2....4..3....3..4....0..1

..0..1....2..3....2..1....1..0....2..3....2..4....1..1....1..2....2..1....2..2

..2..1....1..0....0..0....1..2....4..3....2..3....2..0....1..3....0..1....1..3

..3..4....2..2....2..1....0..0....1..2....2..1....1..1....1..2....0..2....2..3

..2..2....1..0....3..0....1..2....3..3....3..4....2..0....0..2....1..2....4..4

CROSSREFS

Column 1 of A234777.

Sequence in context: A064022 A116065 A234777 * A052049 A046378 A187176

Adjacent sequences:  A234767 A234768 A234769 * A234771 A234772 A234773

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 30 2013

STATUS

approved

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Last modified September 18 07:00 EDT 2021. Contains 347510 sequences. (Running on oeis4.)