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Search: id:A101585
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| A101585 |
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Indices of primes in sequence defined by A(0) = 53, A(n) = 10*A(n-1) + 43 for n > 0. |
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+0
1
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| 0, 3, 11, 14, 17, 36, 108, 1727, 2481, 3479, 6576, 9014
(list; graph; listen)
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OFFSET
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1,2
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COMMENT
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Numbers n such that (520*10^n - 43)/9 is prime.
Numbers n such that digit 5 followed by n >= 0 occurrences of digit 7 followed by digit 3 is prime.
Numbers corresponding to terms <= 108 are certified primes.
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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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57773 is prime, hence 3 is a term.
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PROGRAM
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(PARI) a=53; for(n=0, 1000, if(isprime(a), print1(n, ", ")); a=10*a+43)
(PARI) for(n=0, 1000, if(isprime((520*10^n-43)/9), print1(n, ", ")))
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CROSSREFS
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Cf. A000533, A002275.
a(n) = A103020(n) - 1.
Sequence in context: A105290 A158790 A063963 this_sequence A115214 A143029 A022123
Adjacent sequences: A101582 A101583 A101584 this_sequence A101586 A101587 A101588
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KEYWORD
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nonn,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 09 2004
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EXTENSIONS
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Five additional terms, corresponding to probable primes, from Ryan Propper (rpropper(AT)stanford.edu), Jun 22 2005
Edited by T. D. Noe (noe(AT)sspectra.com), Oct 30 2008
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