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A067852
Numbers k that divide prime(k^2) - 1.
2
1, 2, 4, 6, 10, 11, 18, 20, 32, 90, 129, 188, 244, 678, 688, 756, 1081, 1322, 1477, 19758, 21351, 29518, 43187, 49978, 50342, 95708, 182326, 248253
OFFSET
1,2
COMMENTS
a(29) > 3*10^5. - Donovan Johnson, Nov 15 2009
Any further terms are > 10^6. - Lucas A. Brown, Sep 27 2024
EXAMPLE
6 divides prime(6^2)-1 = 150, so 6 is a term of the sequence.
MATHEMATICA
Select[Range[10^4], Mod[Prime[ #^2] - 1, # ] == 0 &]
PROG
(PARI) isok(k) = !((prime(k^2)-1) % k); \\ Michel Marcus, Aug 15 2021
CROSSREFS
KEYWORD
nonn,more,hard
AUTHOR
Joseph L. Pe, Feb 15 2002
EXTENSIONS
a(20)-a(28) from Donovan Johnson, Nov 15 2009
STATUS
approved