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A319505
Numbers k such that 2^(k*(k+1)/2) == -1 (mod k^2).
0
1, 389993, 476729, 2927297, 3048569, 3862529, 3914049, 4755729, 5077209, 7460409, 9009489, 9314009, 11066649, 11981409, 12928289, 13342769, 15371609, 15574449, 22975249, 34429449, 44876649, 57046209, 66358417, 66963369, 79552209, 83006769, 96783929, 99127313, 118462737, 126209609, 128566689, 139745969
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OFFSET
1,2
LINKS
Table of n, a(n) for n=1..32.
PROG
(PARI) isok(n) = Mod(2, n^2)^(n*(n+1)/2)==-1;
CROSSREFS
Cf.
A006125
,
A077816
,
A126884
.
Sequence in context:
A258686
A157739
A233491
*
A106778
A164987
A176765
Adjacent sequences:
A319502
A319503
A319504
*
A319506
A319507
A319508
KEYWORD
nonn
AUTHOR
Altug Alkan
, Sep 21 2018
STATUS
approved
