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A224276 Number of nX3 0..3 arrays with diagonals and rows unimodal and antidiagonals nondecreasing 1
50, 984, 13683, 186516, 2596992, 37128051, 537465766, 7804602744, 113382138975, 1646661944858, 23908590491858, 347099092628781, 5038892410726190, 73149786094975076, 1061918636087967819, 15415943271255819642 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A224281

LINKS

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

FORMULA

Empirical: a(n) = 20*a(n-1) -70*a(n-2) -211*a(n-3) +192*a(n-4) +15174*a(n-5) -36608*a(n-6) -83340*a(n-7) +59774*a(n-8) +2310958*a(n-9) -3620776*a(n-10) -5846720*a(n-11) +390652*a(n-12) +87932540*a(n-13) -70516876*a(n-14) +46329332*a(n-15) +7472696*a(n-16) -557612816*a(n-17) +319521288*a(n-18) -63018416*a(n-19) +17463360*a(n-20) +1046997696*a(n-21) -323677440*a(n-22) -14515200*a(n-23) -56540160*a(n-24) -635904000*a(n-25) for n>26

EXAMPLE

Some solutions for n=3

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

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

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

CROSSREFS

Sequence in context: A324217 A224059 A224045 * A224199 A112890 A231421

Adjacent sequences:  A224273 A224274 A224275 * A224277 A224278 A224279

KEYWORD

nonn

AUTHOR

R. H. Hardin Apr 02 2013

STATUS

approved

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Last modified August 7 19:55 EDT 2022. Contains 355994 sequences. (Running on oeis4.)