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A062586 Numbers n such that k^n - (k-1)^n is prime, where k is 20. 0
5, 17, 109, 1979, 6899, 7331, 18661, 79621, 81649 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

Terms > 1000 are often only strong pseudo-primes.

LINKS

Top probable primes of the form 20^p-19^p

CROSSREFS

Cf. A000043, A057468, A059801, A059802, A062572-A062666.

Sequence in context: A100301 A096178 A084167 * A067710 A197912 A203114

Adjacent sequences:  A062583 A062584 A062585 * A062587 A062588 A062589

KEYWORD

nonn,hard

AUTHOR

Mike Oakes (Mikeoakes2(AT)aol.com), May 18 2001, May 19 2001

EXTENSIONS

Three more terms (18661, 79621 and 81649) found by Jean-Louis Charton in February and March 2011 corresponding to probable primes with 24279, 103590 and 106228 digits.

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Last modified February 15 20:26 EST 2012. Contains 205852 sequences.