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A204735 Number of (n+1)X4 0..1 arrays with rows and columns of permanents of all 2X2 subblocks lexicographically nondecreasing, and all 2X2 permanents nonzero 1
31, 115, 409, 1389, 4658, 15327, 50177, 163232, 530016, 1717764, 5563837, 18012221, 58302070, 188688609, 610642633, 1976129278, 6394969908, 20694674546, 66969565365, 216718343291, 701315733834, 2269506030743, 7344276796657 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A204740

LINKS

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

FORMULA

Empirical: a(n) = 4*a(n-1) +5*a(n-2) -30*a(n-3) -3*a(n-4) +88*a(n-5) -25*a(n-6) -126*a(n-7) +60*a(n-8) +88*a(n-9) -52*a(n-10) -24*a(n-11) +16*a(n-12)

EXAMPLE

Some solutions for n=4

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

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

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

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

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

CROSSREFS

Sequence in context: A044663 A142228 A304241 * A254283 A010019 A256650

Adjacent sequences:  A204732 A204733 A204734 * A204736 A204737 A204738

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 18 2012

STATUS

approved

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Last modified December 12 09:36 EST 2019. Contains 329953 sequences. (Running on oeis4.)