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A138758
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Index of A001203(n) (continued fraction for Pi) in A000040 (primes), or 0 if A001203(n) is not prime.
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3
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2, 4, 0, 0, 0, 0, 0, 0, 1, 0, 2, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 0, 2, 6, 0, 0, 1, 0, 0, 0, 0, 1, 1, 0, 2, 3, 0, 0, 0, 0, 0, 4, 0, 1, 2, 4, 0, 1, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 3, 1, 1, 2, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0, 0, 1, 0, 2, 0, 1, 0, 0, 0, 1, 3, 0, 0, 1
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OFFSET
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1,1
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LINKS
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FORMULA
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EXAMPLE
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This sequence starts 2,4,0,0,... since the 1st and 2nd terms of the continued fraction expansion of Pi, A001203 = (3, 7, 15, 1, ...) are the 2nd resp. 4th primes, while the next two terms are not primes.
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PROG
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(PARI) default(realprecision, 1000); t=contfrac(Pi); vector(#t, i, isprime(t[i])*primepi(t[i]))
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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