Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A119337
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A119337 Number triangle T(n,k)=sum{i=0..n, (-1)^(n-i)*C(n,i)*sum{j=0..i-k, C(k,3j)*C(i-k,3j)}}. +0
2
1, 0, 1, 0, -1, 1, 0, 1, -2, 1, 0, -1, 3, -3, 1, 0, 1, -4, 6, -4, 1, 0, -1, 5, -9, 10, -5, 1, 0, 1, -6, 12, -16, 15, -6, 1, 0, -1, 7, -15, 19, -25, 21, -7, 1, 0, 1, -8, 18, -16, 20, -36, 28, -8, 1, 0, -1, 9, -21, 4, 24, 6, -49, 36, -9, 1 (list; table; graph; listen)
OFFSET

0,9

COMMENT

Row sums have g.f. (1+x)/(1-x)^6. Multiply by Pascal's triangle A007318 to get A119335.

FORMULA

Column k has g.f. (x/(1+x))^k*sum{j=0..k, C(k,3j)x^(3j)}

EXAMPLE

Triangle begins

1,

0, 1,

0, -1, 1,

0, 1, -2, 1,

0, -1, 3, -3, 1,

0, 1, -4, 6, -4, 1,

0, -1, 5, -9, 10, -5, 1,

0, 1, -6, 12, -16, 15, -6, 1,

0, -1, 7, -15, 19, -25, 21, -7, 1,

0, 1, -8, 18, -16, 20, -36, 28, -8, 1,

0, -1, 9, -21, 4, 24, 6, -49, 36, -9, 1

CROSSREFS

Sequence in context: A121480 A082601 A077593 this_sequence A110555 A071919 A097805

Adjacent sequences: A119334 A119335 A119336 this_sequence A119338 A119339 A119340

KEYWORD

easy,sign,tabl

AUTHOR

Paul Barry (pbarry(AT)wit.ie), May 14 2006

page 1

Search completed in 0.002 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified November 27 22:38 EST 2009. Contains 167602 sequences.


AT&T Labs Research