Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A138240
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A138240 Expansion of (1/4)(1-sqrt(1-12x)/sqrt(1-4x)). +0
2
0, 1, 6, 40, 296, 2400, 20928, 192768, 1848960, 18277888, 184890368, 1904259072, 19898765312, 210424545280, 2247494172672, 24209586782208, 262696649785344, 2868744309571584, 31504024885002240, 347697247933169664 (list; graph; listen)
OFFSET

0,3

COMMENT

Hankel transform of a(n) is -4^comb(n,2)*A099156(n)=-4^comb(n,2)*[x^n](x/(1-8x+4x^2)).

Hankel transform of a(n+1) is 4^comb(n+1,2)=A053763(n+1).

Hankel transform of a(n+2) is 4^comb(n+1,2)*A102591(n+1)=4^comb(n+1,2)*[x^n](6-4x)/(1-8x+4x^2).

CROSSREFS

Cf. A104498.

Sequence in context: A069720 A005037 A081337 this_sequence A083805 A006387 A014481

Adjacent sequences: A138237 A138238 A138239 this_sequence A138241 A138242 A138243

KEYWORD

easy,nonn

AUTHOR

Paul Barry (pbarry(AT)wit.ie), Mar 07 2008

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 December 16 13:01 EST 2009. Contains 170825 sequences.


AT&T Labs Research