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A130433
Even pseudoprimes to base 3.
17
286, 24046, 232726, 1304446, 1707266, 2232026, 3197806, 3922126, 4446982, 5603326, 5886166, 10123366, 10169926, 12304774, 13658086, 45133726, 47766286, 52249654, 62656126, 75421126, 76254046, 91459126, 91612246, 96956926, 108571606, 139868326, 151513846
OFFSET
1,1
COMMENTS
The first 27 terms (halved) are given in Table 1 by Paszkiewicz and Rotkiewicz. - R. J. Mathar, Aug 22 2012
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..215 (terms below 10^12, calculated from the b-file at A005935; terms 1..68 from Jeppe Stig Nielsen)
Adam Paszkiewicz and Andrzej Rotkiewicz, On a Problem of H. J. A. Duprac, Tatra Mt. Math. Publ. 32 (2005) 15-32, MR2206908.
Eric Weisstein's World of Mathematics, Fermat Pseudoprime.
MATHEMATICA
Do[ f=PowerMod[ 3, 2n-1, 2n ]; If[ f==1, Print[ 2n ] ], {n, 2, 7000000} ]
PROG
(PARI) forstep(n=4, 10^10, 2, Mod(3, n)^(n-1)==1 && print1(n, ", ")) \\ Jeppe Stig Nielsen, Apr 25 2018
CROSSREFS
Even terms of A005935.
Terms of A122780 that are congruent to 2 or 4 modulo 6.
Sequence in context: A117994 A221431 A306144 * A140926 A295447 A203049
KEYWORD
nonn
AUTHOR
Alexander Adamchuk, May 26 2007, Jun 17 2007
EXTENSIONS
More terms from Alexander Adamchuk, Jun 17 2007
a(25)-a(27) from Jeppe Stig Nielsen, Apr 25 2018
STATUS
approved