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%I #18 Sep 27 2024 02:12:10
%S 1,2,4,6,10,11,18,20,32,90,129,188,244,678,688,756,1081,1322,1477,
%T 19758,21351,29518,43187,49978,50342,95708,182326,248253
%N Numbers k that divide prime(k^2) - 1.
%C a(29) > 3*10^5. - _Donovan Johnson_, Nov 15 2009
%C Any further terms are > 10^6. - _Lucas A. Brown_, Sep 27 2024
%H Lucas A. Brown, <a href="https://github.com/lucasaugustus/oeis/blob/main/A067852.py">Python program</a>.
%e 6 divides prime(6^2)-1 = 150, so 6 is a term of the sequence.
%t Select[Range[10^4], Mod[Prime[ #^2] - 1, # ] == 0 &]
%o (PARI) isok(k) = !((prime(k^2)-1) % k); \\ _Michel Marcus_, Aug 15 2021
%Y Cf. A000040, A011757, A067851.
%K nonn,more,hard
%O 1,2
%A _Joseph L. Pe_, Feb 15 2002
%E a(20)-a(28) from _Donovan Johnson_, Nov 15 2009