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A111014
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Primes in the sequence A015519.
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1
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OFFSET
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1,1
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COMMENTS
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Is there an infinity of primes in this sequence?
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REFERENCES
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John Derbyshire, Prime Obsession, Joseph Henry Press, April 2004, p. 16.
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LINKS
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FORMULA
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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)).
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MATHEMATICA
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Select[LinearRecurrence[{2, 7}, {0, 1}, 100], PrimeQ] (* Amiram Eldar, Jun 30 2024 *)
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PROG
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(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+.) }
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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STATUS
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approved
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