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Revision History for A205344 (Bold, blue-underlined text is an addition; faded, red-underlined text is a deletion.)

Showing all changes.
Number of length 7 nonnegative integer arrays starting and ending with 0 with adjacent elements unequal but differing by no more than n.
(history; published version)
#8 by Alois P. Heinz at Mon Jun 11 15:52:46 EDT 2018
STATUS

proposed

approved

#7 by Colin Barker at Mon Jun 11 12:20:40 EDT 2018
STATUS

editing

proposed

#6 by Colin Barker at Mon Jun 11 12:20:17 EDT 2018
NAME

Number of length 7 nonnegative integer arrays starting and ending with 0 with adjacent elements unequal but differing by no more than n.

COMMENTS

Row 6 of A205341.

FORMULA

Empirical: a(n) = (44/15)*n^5 - (5/12)*n^4 + (5/12)*n^2 + (31/15)*n.

Conjectures from Colin Barker, Jun 11 2018: (Start)

G.f.: x*(5 + 63*x + 206*x^2 + 73*x^3 + 5*x^4) / (1 - x)^6.

a(n) = 6*a(n-1) - 15*a(n-2) + 20*a(n-3) - 15*a(n-4) + 6*a(n-5) - a(n-6) for n>6.

(End)

EXAMPLE

Some solutions for n=5:

CROSSREFS

Cf. A205341.

AUTHOR

R. H. Hardin , Jan 26 2012

STATUS

approved

editing

#5 by Russ Cox at Sat Mar 31 12:37:06 EDT 2012
AUTHOR

_R. H. Hardin (rhhardin(AT)att.net) _ Jan 26 2012

Discussion
Sat Mar 31
12:37
OEIS Server: https://oeis.org/edit/global/875
#4 by Ron Hardin at Thu Jan 26 10:52:36 EST 2012
STATUS

editing

approved

#3 by Ron Hardin at Thu Jan 26 10:52:33 EST 2012
LINKS

R. H. Hardin, <a href="/A205344/b205344.txt">Table of n, a(n) for n = 1..210</a>

#2 by Ron Hardin at Thu Jan 26 10:52:11 EST 2012
NAME

allocated for Ron HardinNumber of length 7 nonnegative integer arrays starting and ending with 0 with adjacent elements unequal but differing by no more than n

DATA

5, 93, 689, 2912, 8927, 22297, 48335, 94456, 170529, 289229, 466389, 721352, 1077323, 1561721, 2206531, 3048656, 4130269, 5499165, 7209113, 9320208, 11899223, 15019961, 18763607, 23219080, 28483385, 34661965, 41869053, 50228024

OFFSET

1,1

COMMENTS

Row 6 of A205341

FORMULA

Empirical: a(n) = (44/15)*n^5 - (5/12)*n^4 + (5/12)*n^2 + (31/15)*n

EXAMPLE

Some solutions for n=5

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

..1....1....5....3....5....1....1....5....4....3....5....4....5....1....3....4

..6....4...10....6....0....2....4....3....8....6...10....3....8....5....1....7

..8....1....5....1....2....0....8....6....7....5....6....6....7....1....5....6

..7....4....3....5....4....4....6....5....3....3....2....7....5....5....3....7

..4....3....5....2....1....3....1....2....2....1....4....5....1....2....2....3

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

KEYWORD

allocated

nonn

AUTHOR

R. H. Hardin (rhhardin(AT)att.net) Jan 26 2012

STATUS

approved

editing

#1 by Ron Hardin at Thu Jan 26 10:42:25 EST 2012
NAME

allocated for Ron Hardin

KEYWORD

allocated

STATUS

approved