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A128472 a(n) is the smallest prime of the form (2n-1)^k - 2 for k > (2n-1), or 0 if no such number exists. 13
0, 79, 6103515623, 5764799, 31381059607 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
a(6) = 11^22420 - 2 was found by Rick L. Shepherd on Sep 29 2007. It has 23349 decimal digits and it is too large to include.
a(7) through a(12): {771936328432730777189183517369830159827426282764863750131729657829597399846468418688727, 98526125335693359373, 339448671314611904643504117119, 37589973457545958193355599, 1136272165922724266740722458520499, 480250763996501976790165756943039}.
LINKS
Henri Lifchitz and Renaud Lifchitz: PRP Records. Probable Primes Top 10000.
CROSSREFS
Cf. A084714 (smallest prime of the form (2n-1)^k - 2).
Cf. A133856 (least number k > (2n-1) such that (2n-1)^k - 2 is prime).
Sequence in context: A265589 A116327 A060711 * A243432 A093404 A236236
KEYWORD
nonn
AUTHOR
Alexander Adamchuk, Mar 14 2007, Oct 01 2007
EXTENSIONS
Edited by Max Alekseyev, Sep 18 2009
STATUS
approved

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Last modified May 29 04:26 EDT 2024. Contains 372921 sequences. (Running on oeis4.)