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A268420 Number of nX2 0..3 arrays with every repeated value in every row unequal to the previous repeated value, and in every column equal to the previous repeated value, and new values introduced in row-major sequential order. 1
2, 15, 187, 2530, 34195, 448667, 5720450, 71224847, 869969995, 10461568690, 124193817155, 1458609678443, 16976365857602, 196066210076847, 2249518678962747, 25662410911209090, 291308117338854611 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 2 of A268423.

LINKS

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

FORMULA

Empirical: a(n) = 33*a(n-1) -389*a(n-2) +1865*a(n-3) -2461*a(n-4) -3639*a(n-5) +7361*a(n-6) +2407*a(n-7) -5491*a(n-8) -585*a(n-9) +981*a(n-10) -81*a(n-11)

EXAMPLE

Some solutions for n=5

..0..1....0..1....0..1....0..1....0..1....0..1....0..1....0..0....0..1....0..1

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

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

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

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

CROSSREFS

Cf. A268423.

Sequence in context: A052857 A053492 A319834 * A208402 A098343 A052819

Adjacent sequences:  A268417 A268418 A268419 * A268421 A268422 A268423

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 04 2016

STATUS

approved

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Last modified October 5 20:00 EDT 2022. Contains 357261 sequences. (Running on oeis4.)