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Search: id:A101846
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| A101846 |
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Indices of primes in sequence defined by A(0) = 37, A(n) = 10*A(n-1) + 17 for n > 0. |
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+0
1
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OFFSET
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1,2
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COMMENT
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Numbers n such that (350*10^n - 17)/9 is prime.
Numbers n such that digit 3 followed by n >= 0 occurrences of digit 8 followed by digit 7 is prime.
No further terms up to 5000.
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REFERENCES
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Klaus Brockhaus and Walter Oberschelp, Zahlenfolgen mit homogenem Ziffernkern, MNU 59/8 (2006), pp. 462-467.
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EXAMPLE
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3888887 is prime, hence 5 is a term.
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PROGRAM
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(PARI) a=37; for(n=0, 1500, if(isprime(a), print1(n, ", ")); a=10*a+17)
(PARI) for(n=0, 1500, if(isprime((350*10^n-17)/9), print1(n, ", ")))
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CROSSREFS
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Cf. A000533, A002275.
a(n) = A102979(n) - 1.
Adjacent sequences: A101843 A101844 A101845 this_sequence A101847 A101848 A101849
Sequence in context: A066546 A132653 A115544 this_sequence A020761 A047752 A088194
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KEYWORD
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nonn,bref,hard,more
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AUTHOR
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Klaus Brockhaus (klaus-brockhaus(AT)t-online.de) and Walter Oberschelp (oberschelp(AT)informatik.rwth-aachen.de), Dec 20 2004
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