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A111014
Primes in the sequence A015519.
1
2, 11, 149, 2143, 6709949, 446049530175322600739691943
OFFSET
1,1
COMMENTS
Is there an infinity of primes in this sequence?
REFERENCES
John Derbyshire, Prime Obsession, Joseph Henry Press, April 2004, p. 16.
LINKS
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)).
MATHEMATICA
Select[LinearRecurrence[{2, 7}, {0, 1}, 100], PrimeQ] (* Amiram Eldar, Jun 30 2024 *)
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
Cf. A015519.
Sequence in context: A046912 A185245 A006122 * A171184 A297676 A049462
KEYWORD
easy,nonn
AUTHOR
Cino Hilliard, Oct 02 2005
STATUS
approved