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A203881 Number of (n+1)X3 0..6 arrays with every 2X2 subblock having equal diagonal elements or equal antidiagonal elements 1
8281, 254359, 7501753, 222645367, 6601376089, 195759462871, 5804976472057, 172139217677623, 5104567195084441, 151369391916622999, 4488665070837227833, 133105602855424669687, 3947075851161154183129, 117045469473077458995031 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 2 of A203887

LINKS

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

FORMULA

Empirical: a(n) = 25*a(n-1) +138*a(n-2)

EXAMPLE

Some solutions for n=4

..0..5..2....4..1..5....4..0..4....1..2..1....2..0..1....0..0..5....4..5..3

..5..0..5....5..4..1....1..4..3....1..1..5....2..2..0....5..0..0....3..4..5

..2..5..6....2..5..4....5..1..4....5..1..1....6..2..2....3..5..0....1..3..4

..3..2..5....5..1..5....6..5..1....3..5..1....3..6..2....1..3..5....1..1..3

..3..3..2....3..5..5....4..6..5....2..3..5....5..3..6....1..1..3....1..6..1

CROSSREFS

Sequence in context: A188101 A157731 A064014 * A145527 A054215 A031679

Adjacent sequences:  A203878 A203879 A203880 * A203882 A203883 A203884

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 07 2012

STATUS

approved

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Last modified July 28 12:23 EDT 2014. Contains 244997 sequences.