login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A200555 Number of -n..n arrays x(0..4) of 5 elements with zero sum and nonzero second differences. 1
26, 280, 1184, 3396, 7778, 15476, 27806, 46346, 72902, 109528, 158422, 222162, 303412, 405134, 530518, 683014, 866156, 1083954, 1340420, 1639900, 1986968, 2386470, 2843276, 3362828, 3950486, 4611980, 5353268, 6180592, 7100158, 8118840 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 3 of A200553.

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..200

FORMULA

Empirical: a(n) = a(n-1) +2*a(n-2) -3*a(n-4) -3*a(n-5) +3*a(n-6) +3*a(n-7) -2*a(n-9) -a(n-10) +a(n-11).

Empirical g.f.: 2*x*(13 + 127*x + 426*x^2 + 826*x^3 + 1046*x^4 + 912*x^5 + 544*x^6 + 205*x^7 + 37*x^8 + 4*x^9) / ((1 - x)^5*(1 + x)^2*(1 + x + x^2)^2). - Colin Barker, May 21 2018

EXAMPLE

Some solutions for n=3:

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

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

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

..2....2....1...-2....1...-3....1...-2....2...-1....2....1...-1...-3....1....2

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

CROSSREFS

Cf. A200553.

Sequence in context: A186261 A006045 A022686 * A130901 A336732 A227332

Adjacent sequences:  A200552 A200553 A200554 * A200556 A200557 A200558

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 19 2011

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 22 09:12 EDT 2022. Contains 353941 sequences. (Running on oeis4.)