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A218584
Numbers n such that 2^A000010(n*x) == 1 (mod (n*x)^2), where x = 3837523 is the product of the first 2 Wieferich primes 1093 and 3511.
1
1, 3, 5, 7, 9, 13, 15, 21, 27, 35, 39, 45, 63, 65, 81, 91, 105, 117, 135, 169, 189, 195, 273, 315, 351, 405, 455, 507, 567, 585, 819, 845, 945, 1053, 1183, 1365, 1521, 1701, 1755, 2457, 2535, 2835, 3159, 3549, 4095, 4563, 5265, 5915, 7371, 7605, 8505, 10647
OFFSET
1,2
COMMENTS
3837523*a(n) is a term in A077816.
If this sequence is finite, then there are finitely many Wieferich primes (A001220).
LINKS
Arkadiusz Wesolowski, Table of n, a(n) for n = 1..74
MATHEMATICA
x = 3837523; Select[Range[1, 10647, 2], PowerMod[2, EulerPhi[#*x], (#*x)^2] == 1 &]
PROG
(PARI) is(n)=Mod(2, (3837523*n)^2)^eulerphi(3837523*n)==1 \\ Charles R Greathouse IV, Mar 05 2013
CROSSREFS
Sequence in context: A114513 A191186 A174572 * A191182 A177855 A003524
KEYWORD
nonn
AUTHOR
STATUS
approved