login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A096548 Difference between the smallest 10^n-digit prime and 10^(10^n-1). 3
7, 289, 7, 33603, 309403, 593499 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Daniel Heuer found a(5) in 2004 by sieving up to 2^33 and then checking ~8000 candidates with pfgw-linux. Proving primality of 10^99999+309403 is beyond current (2004) technology.
a(6) was found by Kenneth Pedersen, Peter Kaiser, and Patrick De Geest. - Charles R Greathouse IV, Feb 11 2013
LINKS
Chris K. Caldwell, The largest known primes.
Chris K. Caldwell, 10^999 + 7, related to a(3).
Chris K. Caldwell, 10^9999 + 33603, related to a(4).
factordb.com, 10^999 + 7, contains primality certificate related to a(3).
factordb.com, 10^9999 + 33603, contains primality certificate related to a(4).
Patrick De Geest, 10^999999 + y, history of a(6).
Henri Lifchitz, Renaud Lifchitz, Probable Primes Top 10000.
Henri Lifchitz, Renaud Lifchitz, 10^99999 + 309403, related to a(5).
Henri Lifchitz, Renaud Lifchitz, 10^999999 + 593499, related to a(6).
Hugo Pfoertner, Paul Underwood, Mike Oakes, Daniel Heuer, Smallest 100000-digit prime?, digest of 7 messages in primeform Yahoo group, Jul 8, 2004. [Cached copy]
FORMULA
a(n) = nextprime(10^(10^n-1)) - 10^(10^n-1) = A007920(10^A002283(n)). - Jeppe Stig Nielsen, Jan 23 2021
EXAMPLE
a(1)=7 because the smallest ten-digit prime is 1000000007.
a(2)=289 because the smallest 100-digit prime is 10^99+289.
CROSSREFS
Cf. A033873.
Sequence in context: A009503 A209889 A176072 * A160072 A137435 A220241
KEYWORD
nonn,base,more,hard
AUTHOR
Hugo Pfoertner, Jul 06 2004
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified February 22 16:01 EST 2024. Contains 370256 sequences. (Running on oeis4.)