login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A188349 Number of arrangements of n+1 numbers x(i) in -n..n with the sum of x(i)*x(i+1) equal to zero 0
5, 45, 257, 4201, 45801, 1171345, 25217201, 870473329, 30807035021, 1370460938381 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Diagonal of A188358

LINKS

Table of n, a(n) for n=1..10.

EXAMPLE

Some solutions for n=4

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

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

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

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

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

CROSSREFS

Sequence in context: A079139 A269911 A249638 * A302526 A303408 A241275

Adjacent sequences:  A188346 A188347 A188348 * A188350 A188351 A188352

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 28 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 | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified September 24 09:10 EDT 2021. Contains 347630 sequences. (Running on oeis4.)