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A092994 Smallest prime of the form concatenation of prime(n) with itself followed by a 7, or 0 if no such prime exists. 4
227, 37, 557, 0, 11117, 137, 17171717171717171717171717171717171717171717171717177, 197, 23232323232323237, 29297, 317, 0, 41414141414141414141414141414141414141414141417 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
a(12)=0 since the concatenation of 37 with itself, followed by a 7, is always composite. a(14), the term relative to 43, is a prime with 1089 digits. - Giovanni Resta, Apr 07 2006
LINKS
CROSSREFS
Sequence in context: A251500 A050847 A098247 * A031513 A078765 A179141
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Mar 28 2004
EXTENSIONS
More terms from Giovanni Resta, Apr 07 2006
STATUS
approved

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Last modified April 23 08:33 EDT 2024. Contains 371905 sequences. (Running on oeis4.)