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A111014 Primes in the sequence A015519. 0
2, 11, 149, 2143, 6709949, 446049530175322600739691943 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Is there an infinity of primes in this sequence?

REFERENCES

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

LINKS

Table of n, a(n) for n=1..6.

FORMULA

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)).

PROG

(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+.) }

CROSSREFS

Sequence in context: A046912 A185245 A006122 * A171184 A297676 A049462

Adjacent sequences:  A111011 A111012 A111013 * A111015 A111016 A111017

KEYWORD

easy,nonn,frac

AUTHOR

Cino Hilliard, Oct 02 2005

STATUS

approved

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Last modified August 25 05:19 EDT 2019. Contains 326318 sequences. (Running on oeis4.)