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A067733 Numbers k such that phi(prime(k)-1) == 0 (mod k). 0
1, 12, 540, 1024, 1072, 1092, 1320, 1408, 4272, 16200, 29568, 40082, 43740, 56592, 123192, 251736, 265440, 276000, 664320, 725760, 758560, 771264, 2101248, 3195192, 6592704, 7243050, 7464960, 8755680, 10553502, 11715840, 14135296, 19952730, 20058720, 21672288 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
MATHEMATICA
Select[Range[42000], Mod[EulerPhi[Prime[ # ] - 1], # ] == 0 &]
PROG
(PARI) for(k=1, 2600000, if(eulerphi(prime(k)-1)%k==0, print1(k, ", ")))
CROSSREFS
Sequence in context: A296685 A281030 A282589 * A353194 A285748 A184423
KEYWORD
nonn
AUTHOR
Benoit Cloitre, Feb 05 2002
EXTENSIONS
More terms from Klaus Brockhaus, Feb 13 2002
More terms from Jinyuan Wang, Apr 05 2020
STATUS
approved

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Last modified June 13 05:35 EDT 2024. Contains 373366 sequences. (Running on oeis4.)