A205228 - OEIS

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A205228

Number of (n+1) X 2 0..2 arrays with rows and columns of permanents of all 2 X 2 subblocks lexicographically nondecreasing, and all 2 X 2 permanents nonzero.

56, 266, 1187, 4584, 17010, 58892, 198325, 642908, 2043150, 6344716, 19418611, 58538770, 174569904, 515123368, 1507602967, 4378408682, 12635495950, 36252368030, 103495137889, 294126992350, 832586122466, 2348335515958

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OFFSET

1,1

COMMENTS

Column 1 of A205235.

LINKS

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

FORMULA

Empirical: a(n) = 5*a(n-1) +8*a(n-2) -69*a(n-3) +389*a(n-5) -198*a(n-6) -1143*a(n-7) +865*a(n-8) +1830*a(n-9) -1686*a(n-10) -1468*a(n-11) +1612*a(n-12) +376*a(n-13) -616*a(n-14) +96*a(n-15).

EXAMPLE

Some solutions for n=4

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

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

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

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

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

CROSSREFS

Cf. A205235.

Sequence in context: A158487 A212778 A205235 * A110554 A253922 A220015

Adjacent sequences: A205225 A205226 A205227 * A205229 A205230 A205231

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 24 2012

STATUS

approved