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A062588 Numbers n such that 22^n - 21^n is prime. 1
2, 127, 877 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

All terms are prime.

No other terms less than 10^5. - Robert Price, May 28 2012

LINKS

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

PROG

(PARI) is(n)=ispseudoprime(22^n-21^n) \\ Charles R Greathouse IV, Jun 12 2017

CROSSREFS

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

Sequence in context: A065381 A274123 A141928 * A125634 A075596 A092832

Adjacent sequences:  A062585 A062586 A062587 * A062589 A062590 A062591

KEYWORD

nonn,hard,bref,more

AUTHOR

Mike Oakes, May 18 2001, May 19 2001

STATUS

approved

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Last modified May 25 11:17 EDT 2019. Contains 323539 sequences. (Running on oeis4.)