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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. 0
0, 46, 68, 98, 574, 714, 2178 (list; graph; refs; listen; history; 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.

REFERENCES

Klaus Brockhaus and Walter Oberschelp, Zahlenfolgen mit homogenem Ziffernkern, MNU 59/8 (2006), pp. 462-467.

LINKS

Makoto Kamada, Factorizations of near-repdigit numbers.

EXAMPLE

59 is prime, hence 0 is a term.

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

Cf. A000533, A002275.

a(n) = A103012(n) - 1.

Sequence in context: A020175 A118698 A103381 * A051413 A167283 A085434

Adjacent sequences:  A101574 A101575 A101576 * A101578 A101579 A101580

KEYWORD

nonn,more

AUTHOR

Klaus Brockhaus (klaus-brockhaus(AT)t-online.de) 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

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Last modified February 15 23:53 EST 2012. Contains 205860 sequences.