login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A211610 Sum_{k=1..n-1} binomial (2*k, k)^n. 2
4, 224, 161312, 1683907808, 256213978094784, 575112148876911852416, 19248204431728945392010740480, 9687459136669902998216039379883774976, 73815961078227084527800998811241905249902260224, 8562177846610881578580018959490439733543225146878872883200 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

COMMENTS

2^n divides a(n).

p divides a(p) for prime p of the form p = 6k + 1.

LINKS

Table of n, a(n) for n=2..11.

FORMULA

a(n) = Sum[ Binomial[2 k, k]^n, {k, 1, n - 1}].

a(n) ~ exp(3/8) * 4^(n^2-n) / (Pi^(n/2) * n^(n/2)). - Vaclav Kotesovec, Mar 03 2014

MATHEMATICA

Table[ Sum[ Binomial[2 k, k]^n, {k, 1, n - 1}], {n, 2, 13}]

CROSSREFS

Cf. A211611, A238717.

Sequence in context: A259460 A227822 A052209 * A042539 A182484 A159281

Adjacent sequences:  A211607 A211608 A211609 * A211611 A211612 A211613

KEYWORD

nonn

AUTHOR

Alexander Adamchuk, Apr 17 2012

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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified February 24 18:24 EST 2018. Contains 299628 sequences. (Running on oeis4.)