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A062594
Numbers k such that 28^k - 27^k is prime.
0
3, 5, 19, 31, 257, 773
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OFFSET
1,1
COMMENTS
Terms > 1000 are often only strong pseudoprimes.
a(7) > 10^5. -
Robert Price
, Sep 04 2012
LINKS
Table of n, a(n) for n=1..6.
PROG
(PARI) is(n)=ispseudoprime(28^n-27^n) \\
Charles R Greathouse IV
, Jun 13 2017
CROSSREFS
Cf.
A000043
,
A057468
,
A059801
,
A059802
,
A062572
-
A062666
.
Sequence in context:
A355253
A068990
A228471
*
A128027
A128066
A273020
Adjacent sequences:
A062591
A062592
A062593
*
A062595
A062596
A062597
KEYWORD
nonn
,
hard
AUTHOR
Mike Oakes
, May 18 2001, May 19 2001
STATUS
approved
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Last modified April 24 18:17 EDT 2024. Contains 371962 sequences. (Running on oeis4.)