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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A137157 G.f.: 1 = Sum_{n>=0} a(n)*x^n/(1+x)^(2*2^n). 4
1, 2, 5, 24, 239, 4920, 206727, 17568408, 3003763243, 1030272816360, 707851744149198, 973425618916674288, 2678332881795756783639, 14741522294008025924154864, 162290544340043699103996962253 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Equals unsigned column 1 of triangle A137156.

LINKS

Table of n, a(n) for n=0..14.

PROG

(PARI) {a(n)=polcoeff(1-sum(k=0, n-1, a(k)*x^k/(1+x+x*O(x^n))^(2^(k+1)) ), n)}

CROSSREFS

Cf. A137156; A001192, A137158, A137159, A137160.

Sequence in context: A012249 A303108 A052808 * A025134 A076534 A095708

Adjacent sequences:  A137154 A137155 A137156 * A137158 A137159 A137160

KEYWORD

nonn

AUTHOR

Paul D. Hanna, Jan 24 2008

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 May 24 00:38 EDT 2019. Contains 323528 sequences. (Running on oeis4.)