login
This site is supported by donations to The OEIS Foundation.

 

Logo

Annual Appeal: Please make a donation to keep the OEIS running. In 2018 we replaced the server with a faster one, added 20000 new sequences, and reached 7000 citations (often saying "discovered thanks to the OEIS").
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A141343 Riordan array (1,x/sqrt(2-sqrt(1+4x)). 2
1, 0, 1, 0, 2, 1, 0, 2, 4, 1, 0, 4, 8, 6, 1, 0, 2, 16, 18, 8, 1, 0, 12, 24, 44, 32, 10, 1, 0, -12, 48, 90, 96, 50, 12, 1, 0, 72, 48, 180, 240, 180, 72, 14, 1, 0, -190, 160, 308, 544, 530, 304, 98, 16, 1, 0, 700, -40, 600, 1120, 1372, 1032, 476, 128 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,5

COMMENTS

Factorizes as (1,xc(-x))*(1,x(1+x)/(1-2x)) where c(x) is the g.f. of A000108.

Row sums are A141344.

Triangle T(n,k), 0<=k<=n, read by rows, given by [0, 2, -1, -1, -1, -1, -1, -1, -1, ...] DELTA [1, 0, 0, 0, 0, 0, 0, ...] where DELTA is the operator defined in A084938. - Philippe Deléham, Nov 15 2008

LINKS

Table of n, a(n) for n=0..63.

EXAMPLE

Triangle begins

1,

0, 1,

0, 2, 1,

0, 2, 4, 1,

0, 4, 8, 6, 1,

0, 2, 16, 18, 8, 1,

0, 12, 24, 44, 32, 10, 1,

0, -12, 48, 90, 96, 50, 12, 1

CROSSREFS

Sequence in context: A227341 A098542 A320019 * A256678 A066709 A258051

Adjacent sequences:  A141340 A141341 A141342 * A141344 A141345 A141346

KEYWORD

easy,sign,tabl

AUTHOR

Paul Barry, Jun 26 2008

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 December 12 14:43 EST 2018. Contains 318076 sequences. (Running on oeis4.)