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A255387 Primes of the form 141^k - 140^k. 0
281, 59221, 769449701919846533025514621 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(4) has 372 digits. - Vincenzo Librandi, Feb 22 2015

The values of k are 2, 3, 13, 173, ... - Jinyuan Wang, May 30 2020

LINKS

Table of n, a(n) for n=1..3.

Michael P. May, On the Existence and Frequency Distribution of the Shell Primes, arXiv preprint arXiv:1510.01028 [math.CO], 2015.

MATHEMATICA

Select[Table[141^n - 140^n, {n, 1000}], PrimeQ] (* Vincenzo Librandi, Feb 22 2015 *)

PROG

(MAGMA) [a: n in [0..600] | IsPrime(a) where a is 141^n-140^n]; // Vincenzo Librandi, Feb 22 2015

(PARI) select(m->ispseudoprime(m), vector(20, k, 141^k-140^k)) \\ Jinyuan Wang, May 30 2020

CROSSREFS

Cf. A254298.

Sequence in context: A270964 A185710 A242982 * A320706 A114804 A250580

Adjacent sequences:  A255384 A255385 A255386 * A255388 A255389 A255390

KEYWORD

nonn

AUTHOR

Michael P. May, Feb 21 2015

STATUS

approved

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Last modified August 10 02:02 EDT 2020. Contains 336365 sequences. (Running on oeis4.)