Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A101269
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A101269 a(1)=0, a(2)=1 a(n+2)=(8*n^2+2*n+1)*a(n+1)-2*n*(2*n-1)^3*a(n). +0
3
0, 1, 11, 299, 15371, 1285371, 159158691, 27376820379, 6246962876475, 1826295061189275, 665694890795056275, 296004348848796457275, 157710301268790933578475, 99189386694727572925906875 (list; graph; listen)
OFFSET

1,3

FORMULA

a(n+1)=(2*n)!*{2*G*binomial(2*n, n)/4^n- integral(t=0, infty, t/cosh(t)^(2*n+1))} where G=0.915965594... is Catalan's constant

Contribution from Johannes W. Meijer (meijgia(AT)hotmail.com), May 24 2009: (Start)

a(n) = (2*n-4)!+(2*n-3)^2*a(n-1) for n= 2, 3, ... with a(1) =0.

(End)

PROGRAM

(PARI) a(n)=if(n<3, (n+1)%2, (8*(n-2)^2+2*(n-2)+1)*a(n-1)-2*(n-2)*(2*(n-2)-1)^3*a(n-2)) - Benoit Cloitre (benoit7848c(AT)orange.fr), Dec 02 2005

CROSSREFS

Cf. A006752.

Contribution from Johannes W. Meijer (meijgia(AT)hotmail.com), May 24 2009: (Start)

Equals for n>=1 the first left hand column of the Beta triangle A160480. The second left hand column is A160482.

(End)

Sequence in context: A165390 A067424 A001538 this_sequence A012184 A012027 A002114

Adjacent sequences: A101266 A101267 A101268 this_sequence A101270 A101271 A101272

KEYWORD

nonn

AUTHOR

Benoit Cloitre (benoit7848c(AT)orange.fr), Dec 18 2004

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 22 20:51 EST 2009. Contains 167312 sequences.


AT&T Labs Research