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A292780
Odd numbers k such that 2^d(k) == d(k) (mod k).
1
1, 1365, 6946975, 160559525, 324148475
OFFSET
1,2
LINKS
Robert Israel, 51 terms of the sequence (it is possible that this list is missing some terms, so it is not a b-file)
EXAMPLE
1365 = 3*5*7*13 is a term because d(1365) = 2^4 and 2^16 == 16 (mod 3*5*7*13).
PROG
(PARI) isok(n) = (n%2==1) && (dn=numdiv(n)) && (Mod(2, n)^dn == dn); \\ Michel Marcus, Feb 25 2019
CROSSREFS
Cf. A000005.
Sequence in context: A022204 A015405 A295466 * A180089 A020409 A231268
KEYWORD
nonn,more
AUTHOR
Altug Alkan, Sep 23 2017
STATUS
approved