The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.



(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A047073 Sum{T(i,n-i): i=0,1,...,n}, array T as in A047072. 3


%S 1,2,4,4,8,12,24,40,80,140,280,504,1008,1848,3696,6864,13728,25740,

%T 51480,97240,194480,369512,739024,1410864,2821728,5408312,10816624,

%U 20801200,41602400,80233200,160466400,310235040,620470080,1202160780

%N Sum{T(i,n-i): i=0,1,...,n}, array T as in A047072.

%F G.f.: 1+sqrt((1+2x)/(1-2x))2x. - _Michael Somos_

%o (PARI) a(n)=if(n<2,max(0,n+1),4*binomial(n-2,n\2-1))

%Y 2*A063886(n)=a(n+1).

%K nonn

%O 0,2

%A _Clark Kimberling_

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 September 29 17:04 EDT 2020. Contains 337432 sequences. (Running on oeis4.)