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Revision History for A221682 (Bold, blue-underlined text is an addition; faded, red-underlined text is a deletion.)

Showing all changes.
Number of 0..7 arrays of length n with each element differing from at least one neighbor by 1 or less, starting with 0.
(history; published version)
#9 by Alois P. Heinz at Thu Oct 19 07:41:30 EDT 2017
STATUS

proposed

approved

#8 by Michel Marcus at Thu Oct 19 05:44:04 EDT 2017
STATUS

editing

proposed

#7 by Michel Marcus at Thu Oct 19 05:44:00 EDT 2017
AUTHOR

R. H. Hardin , Jan 22 2013

STATUS

proposed

editing

#6 by Colin Barker at Thu Oct 19 05:41:59 EDT 2017
STATUS

editing

proposed

#5 by Colin Barker at Thu Oct 19 05:41:53 EDT 2017
NAME

Number of 0..7 arrays of length n with each element differing from at least one neighbor by 1 or less, starting with 0.

COMMENTS

Column 7 of A221683.

FORMULA

Empirical: a(n) = 5*a(n-1) +3*a(n-2) -16*a(n-3) +65*a(n-4) -14*a(n-5) +23*a(n-6) +2*a(n-7) +8*a(n-8).

Empirical g.f.: x^2*(2 - 5*x + 13*x^2 - 4*x^3 + 5*x^4 + 2*x^5 + 2*x^6) / (1 - 5*x - 3*x^2 + 16*x^3 - 65*x^4 + 14*x^5 - 23*x^6 - 2*x^7 - 8*x^8). - Colin Barker, Oct 19 2017

STATUS

approved

editing

#4 by R. H. Hardin at Tue Jan 22 06:29:32 EST 2013
STATUS

editing

approved

#3 by R. H. Hardin at Tue Jan 22 06:29:20 EST 2013
LINKS

R. H. Hardin, <a href="/A221682/b221682.txt">Table of n, a(n) for n = 1..210</a>

#2 by R. H. Hardin at Tue Jan 22 06:29:03 EST 2013
NAME

allocated for R. H. Hardin

Number of 0..7 arrays of length n with each element differing from at least one neighbor by 1 or less, starting with 0

DATA

0, 2, 5, 44, 199, 1182, 6102, 33710, 180382, 980490, 5289023, 28634131, 154747076, 837016897, 4525504274, 24472972752, 132331839901, 715586695597, 3869459738102, 20923925463760, 113144565987295, 611822365490334

OFFSET

1,2

COMMENTS

Column 7 of A221683

FORMULA

Empirical: a(n) = 5*a(n-1) +3*a(n-2) -16*a(n-3) +65*a(n-4) -14*a(n-5) +23*a(n-6) +2*a(n-7) +8*a(n-8)

EXAMPLE

Some solutions for n=6

..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0

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

..0....4....0....6....1....7....7....1....2....0....1....0....1....5....0....6

..2....3....1....7....2....6....6....3....2....1....2....0....3....4....6....5

..1....3....1....2....6....0....3....2....3....6....2....1....3....1....5....6

..2....2....1....3....7....1....3....2....2....6....3....0....2....2....5....7

KEYWORD

allocated

nonn

AUTHOR

R. H. Hardin Jan 22 2013

STATUS

approved

editing

#1 by R. H. Hardin at Tue Jan 22 06:20:21 EST 2013
NAME

allocated for R. H. Hardin

KEYWORD

allocated

STATUS

approved