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A101577 Indices of primes in sequence defined by A(0) = 59, A(n) = 10*A(n-1) - 51 for n > 0. 1
0, 46, 68, 98, 574, 714, 2178, 10540 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Numbers n such that (480*10^n + 51)/9 is prime.
Numbers n such that digit 5 followed by n >= 0 occurrences of digit 3 followed by digit 1 is prime.
Numbers corresponding to terms <= 714 are certified primes.
a(9) > 10^5. - Robert Price, Sep 08 2015
REFERENCES
Klaus Brockhaus and Walter Oberschelp, Zahlenfolgen mit homogenem Ziffernkern, MNU 59/8 (2006), pp. 462-467.
LINKS
FORMULA
a(n) = A103012(n+1) - 1.
EXAMPLE
59 is prime, hence 0 is a term.
MATHEMATICA
Select[Range[0, 10000], PrimeQ[(480*10^# + 51)/9] &] (* Robert Price, Sep 08 2015 *)
PROG
(PARI) a=59; for(n=0, 1000, if(isprime(a), print1(n, ", ")); a=10*a-51)
(PARI) for(n=0, 1000, if(isprime((480*10^n+51)/9), print1(n, ", ")))
CROSSREFS
Sequence in context: A118698 A350203 A103381 * A051413 A167283 A085434
KEYWORD
nonn,more
AUTHOR
Klaus Brockhaus and Walter Oberschelp (oberschelp(AT)informatik.rwth-aachen.de), Dec 09 2004
EXTENSIONS
More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 01 2008
a(8) from Kamada data by Ray Chandler, Apr 30 2015
STATUS
approved

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Last modified June 24 00:02 EDT 2024. Contains 373661 sequences. (Running on oeis4.)