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!)
A124821 Number triangle T(n,k)=(-1)^(n-k)*(3k+2)*C(3n+1, n-k)/(2n+k+2). 1
1, -2, 1, 7, -5, 1, -30, 25, -8, 1, 143, -130, 52, -11, 1, -728, 700, -320, 88, -14, 1, 3876, -3876, 1938, -627, 133, -17, 1, -21318, 21945, -11704, 4235, -1078, 187, -20, 1, 120175, -126500, 70840, -27830, 8050, -1700 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Inverse of number triangle A124819. Row sums are (-1)^n*A001764(n).

LINKS

Table of n, a(n) for n=0..41.

Paul Drube, Generalized Path Pairs and Fuss-Catalan Triangles, arXiv:2007.01892 [math.CO], 2020. See Figure 4 p. 8. (up to signs).

EXAMPLE

Triangle begins

1,

-2, 1,

7, -5, 1,

-30, 25, -8, 1,

143, -130, 52, -11, 1,

-728, 700, -320, 88, -14, 1,

3876, -3876, 1938, -627, 133, -17, 1

CROSSREFS

Cf. A124019.

Sequence in context: A339000 A248811 A048505 * A104030 A206533 A262057

Adjacent sequences:  A124818 A124819 A124820 * A124822 A124823 A124824

KEYWORD

easy,sign,tabl

AUTHOR

Paul Barry, Nov 08 2006

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 27 17:05 EDT 2021. Contains 347693 sequences. (Running on oeis4.)