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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A111014 Primes in the sequence A015519. 0

%I

%S 2,11,149,2143,6709949,446049530175322600739691943

%N Primes in the sequence A015519.

%C Is there an infinity of primes in this sequence?

%D Prime Obsession, John Derbyshire, Joseph Henry Press, April 2004, p 16.

%F Given a(0)=1, b(0)=1 then for i=1, 2, .. a(i)/b(i) = (a(i-1)+2*b(i-1)) /(a(i-1) + b(i-1)).

%o (PARI) primenum(n,k,typ) = \ k=mult,typ=1 num,2 denom. output prime num or denom. { local(a,b,x,tmp,v); a=1;b=1; for(x=1,n, tmp=b; b=a+b; a=k*tmp+a; if(typ==1,v=a,v=b); if(isprime(v),print1(v","); ) ); print(); print(a/b+.) }

%K easy,nonn,frac

%O 1,1

%A _Cino Hilliard_, Oct 02 2005

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 20 05:51 EDT 2019. Contains 327212 sequences. (Running on oeis4.)