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A291602
Composite integers k satisfying 2^d == 2^(k/d) (mod k) for all d|k and that are not Super-Poulet (A050217).
3
1105, 13981, 68101, 137149, 149281, 158369, 266305, 285541, 423793, 617093, 625921, 852841, 1052503, 1052929, 1104349, 1128121, 1306801, 1746289, 2940337, 3048841, 3828001, 4072729, 4154161, 4209661, 4682833, 6183601, 6236473, 6617929, 7803769, 9106141, 11157721, 11644921, 12096613, 12932989, 13554781
OFFSET
1,1
COMMENTS
The set difference of A291601 and A050217.
Terms that are Carmichael numbers (A002997) are given by A291612. - Altug Alkan, Aug 27 2017
LINKS
PROG
(PARI) is(k) = {if(k == 1 || !(k%2) || isprime(k), return(0)); my(issp = 1); fordiv(k, d, if(Mod(2, d)^d != 2, issp = 0; break)); if(!issp, fordiv(k, d, if(d^2 <= k && Mod(2, k)^d != Mod(2, k)^(k/d), return(0))); 1, 0); } \\ Amiram Eldar, Apr 22 2024
CROSSREFS
KEYWORD
nonn
AUTHOR
Max Alekseyev, Aug 27 2017
STATUS
approved