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A255659 Number of length n+7 0..3 arrays with at most two downsteps in every 7 consecutive neighbor pairs 1
28722, 83752, 265430, 864924, 2816673, 9169016, 29577432, 92530816, 286454024, 900260308, 2873064972, 9187712072, 29298245258, 93413733472, 297026093532, 940176646792, 2973476370798, 9435365703664, 30019424281120, 95485615550472 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 7 of A255660

LINKS

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

FORMULA

Empirical: a(n) = 4*a(n-1) -6*a(n-2) +4*a(n-3) +30*a(n-4) -72*a(n-5) +58*a(n-6) +872*a(n-7) -2121*a(n-8) +1748*a(n-9) -492*a(n-10) -13640*a(n-11) +26816*a(n-12) -13536*a(n-13) -232948*a(n-14) +493540*a(n-15) -280547*a(n-16) -33840*a(n-17) +1271000*a(n-18) -2599020*a(n-19) +2012477*a(n-20) +14744048*a(n-21) -38149820*a(n-22) +32418288*a(n-23) -9358211*a(n-24) -17204016*a(n-25) +20480444*a(n-26) -6417756*a(n-27) -25522136*a(n-28) +31264272*a(n-29) -10417774*a(n-30) -104220*a(n-31) +17617480*a(n-32) -9721216*a(n-33) -6417184*a(n-34) +19052720*a(n-35) -11470236*a(n-36) -3073784*a(n-37) +2563240*a(n-38) -4701200*a(n-39) +5023520*a(n-40) -1940960*a(n-41) -2778800*a(n-42) +3580160*a(n-43) -1109600*a(n-44) +16000*a(n-45) +88000*a(n-46) +22400*a(n-47) +10000*a(n-48)

EXAMPLE

Some solutions for n=2

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

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

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

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

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

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

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

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

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

CROSSREFS

Cf. A255660

Sequence in context: A145686 A224576 A234835 * A213460 A043660 A296814

Adjacent sequences:  A255656 A255657 A255658 * A255660 A255661 A255662

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 01 2015

STATUS

approved

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Last modified September 26 17:30 EDT 2021. Contains 347670 sequences. (Running on oeis4.)