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%I #27 May 30 2024 01:30:48
%S 1,8,256,500,864,8192,9826,16000,27648,54000,132651,209952,246924,
%T 262144,314432,333396,512000,884736,1061208,1562500,1728000,6718464,
%U 7002306,7294032,7901568,8388608,8541936,10061824,10668672,13122000,13564278,15432750,16384000
%N Numbers k such that k * phi(k) is a fifth power.
%C To look for terms it suffices to see if fifth powers have a divisors pair (k, m) such that phi(m) = k. - _David A. Corneth_, May 21 2024
%H David A. Corneth, <a href="/A372670/b372670.txt">Table of n, a(n) for n = 1..8846</a> (first 38 terms from R. J. Mathar)
%F If n is in the sequence and prime p divides n, then p^5*n is in the sequence.
%e 8 * phi(8) = 32 = 2^5.
%o (PARI) isok(n) = ispower(n*eulerphi(n), 5);
%Y Cf. A000584, A002618, A114076.
%K nonn
%O 1,2
%A _Seiichi Manyama_, May 10 2024
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