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A247722 Number of length n+3 0..4 arrays with no disjoint pairs in any consecutive four terms having the same sum 1
440, 1592, 5796, 21152, 77236, 282384, 1032952, 3779018, 13825712, 50587924, 185112244, 677378582, 2478738332, 9070607046, 33193012732, 121467142552, 444499919836, 1626617553810, 5952507849748, 21782859518402, 79713149293808 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A247726

LINKS

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

FORMULA

Empirical: a(n) = 3*a(n-1) -6*a(n-2) +20*a(n-3) +54*a(n-4) -66*a(n-5) +313*a(n-6) -619*a(n-7) -797*a(n-8) -493*a(n-9) -5172*a(n-10) +1690*a(n-11) -2554*a(n-12) -84*a(n-13) +563*a(n-14) +3103*a(n-15) +12407*a(n-16) +10585*a(n-17) +147780*a(n-18) -40884*a(n-19) +31860*a(n-20) -71368*a(n-21) -151570*a(n-22) +112176*a(n-23) +332750*a(n-24) +324290*a(n-25) -1170072*a(n-26) -16160*a(n-27) -274274*a(n-28) +949452*a(n-29) +1863096*a(n-30) -195890*a(n-31) -2817928*a(n-32) -3449516*a(n-33) +2141463*a(n-34) +2233863*a(n-35) +3747347*a(n-36) +474055*a(n-37) -4040991*a(n-38) -2274839*a(n-39) -660322*a(n-40) +2250384*a(n-41) +934278*a(n-42) +180486*a(n-43) -56268*a(n-44) -559872*a(n-45)

EXAMPLE

Some solutions for n=5

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

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

..2....1....2....0....4....4....2....4....2....1....2....4....4....0....1....2

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

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

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

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

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

CROSSREFS

Sequence in context: A072604 A158319 A250879 * A234202 A061626 A187239

Adjacent sequences:  A247719 A247720 A247721 * A247723 A247724 A247725

KEYWORD

nonn

AUTHOR

R. H. Hardin, Sep 23 2014

STATUS

approved

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Last modified December 5 08:36 EST 2021. Contains 349543 sequences. (Running on oeis4.)