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!)
A034269 a(n) = f(n,n+2) where f is given in A034261. 1
0, 1, 11, 76, 435, 2255, 11011, 51688, 236028, 1056210, 4654430, 20266312, 87402185, 374008635, 1590144675, 6724160400, 28303504680, 118665923310, 495820606410, 2065492595400, 8581809094950, 35572994871414, 147149351758926, 607555878211376 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..1000

FORMULA

Appears to be a(n) = 4^(n+1)*Pi^(-1/2)*GAMMA(n+3/2)/GAMMA(n+5)*(n+1)*n*(n^2+3*n+1). - Mark van Hoeij, Oct 30 2011.

MATHEMATICA

Table[n*(n^2+3*n+1)*Binomial[2*n+2, n]/((n+3)*(n+4)), {n, 0, 20}] (* Vaclav Kotesovec, Oct 27 2012 *)

PROG

(PARI) a(n)=n*(n^2+3*n+1)*binomial(2*n+2, n)/((n+3)*(n+4)); \\ Joerg Arndt, May 04 2013

CROSSREFS

Sequence in context: A036427 A122589 A302382 * A256597 A245561 A056914

Adjacent sequences:  A034266 A034267 A034268 * A034270 A034271 A034272

KEYWORD

nonn,easy

AUTHOR

Clark Kimberling

EXTENSIONS

Corrected and extended by N. J. A. Sloane, Apr 21 2000

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 January 28 22:40 EST 2020. Contains 331328 sequences. (Running on oeis4.)