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%I #7 Jun 07 2021 06:51:17
%S 27,243,1377,2187,3125,19683,28125,55233,68445,177147,195625,203125,
%T 239805,253125,453125,823543,907137,1323297,1378125,1464561,1594323,
%U 1953125,2278125,3341637,3572829,5255361,5877117,9034497,9819837,11701053,14348907,17453125,19460393,20503125,22209633,26010621,30074733,44910045
%N Odd numbers k such that A173557(k) divides nonzero A051709(k).
%C Question: Are there any common terms with A345051?
%H <a href="/index/O#opnseqs">Index entries for sequences where odd perfect numbers must occur, if they exist at all</a>
%o (PARI)
%o A051709(n) = ((sigma(n) + eulerphi(n)) - (2*n));
%o A173557(n) = factorback(apply(p -> p-1, factor(n)[, 1]));
%o isA345054(n) = if(!(n%2),0,my(u=A051709(n)); ((u>0)&&(0==(u%A173557(n)))));
%Y Odd terms in A344994.
%Y Cf. A051709, A173557, A345051.
%K nonn
%O 1,1
%A _Antti Karttunen_, Jun 06 2021
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