|
Search: id:A101535
|
|
|
| A101535 |
|
Indices of primes in sequence defined by A(0) = 63, A(n) = 10*A(n-1) + 43 for n > 0. |
|
+0
1
|
| |
|
|
OFFSET
|
1,2
|
|
|
COMMENT
|
Numbers n such that (610*10^n - 43)/9 is prime.
Numbers n such that digit 6 followed by n >= 0 occurrences of digit 7 followed by digit 3 is prime.
Some of the larger entries may only correspond to probable 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
|
673 is prime, hence 1 is a term.
|
|
PROGRAM
|
(PARI) a=63; for(n=0, 2000, if(isprime(a), print1(n, ", ")); a=10*a+43)
(PARI) for(n=0, 2000, if(isprime((610*10^n-43)/9), print1(n, ", ")))
|
|
CROSSREFS
|
Cf. A000533, A002275.
a(n) = A103042(n) - 1.
Sequence in context: A129640 A028382 A131960 this_sequence A010086 A110834 A110842
Adjacent sequences: A101532 A101533 A101534 this_sequence A101536 A101537 A101538
|
|
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 0.004 seconds
|
