|
Search: id:A101528
|
|
|
| A101528 |
|
Indices of primes in sequence defined by A(0) = 63, A(n) = 10*A(n-1) + 13 for n > 0. |
|
+0
1
|
|
| 1, 4, 5, 10, 14, 68, 89, 133, 188, 244, 266, 269, 469, 1574, 2294, 2506, 3511, 3824, 6856
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
COMMENT
|
Numbers n such that (580*10^n - 13)/9 is prime.
Numbers n such that digit 6 followed by n >= 0 occurrences of digit 4 followed by digit 3 is prime.
Numbers corresponding to terms <= 469 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
|
6444443 is prime, hence 5 is a term.
|
|
PROGRAM
|
(PARI) a=63; for(n=0, 1000, if(isprime(a), print1(n, ", ")); a=10*a+13)
(PARI) for(n=0, 1000, if(isprime((580*10^n-13)/9), print1(n, ", ")))
|
|
CROSSREFS
|
Cf. A000533, A002275.
a(n) = A103035(n) - 1.
Sequence in context: A116930 A073119 A002257 this_sequence A119040 A135104 A131780
Adjacent sequences: A101525 A101526 A101527 this_sequence A101529 A101530 A101531
|
|
KEYWORD
|
nonn,hard,more
|
|
AUTHOR
|
Klaus Brockhaus (klaus-brockhaus(AT)t-online.de) and Walter Oberschelp (oberschelp(AT)informatik.rwth-aachen.de), Dec 06 2004
|
|
EXTENSIONS
|
More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 01 2008
|
|
|
Search completed in 0.002 seconds
|
