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%I #12 May 03 2020 13:59:43
%S 1,12,125,451,4612,5412,8313,22165,31815,34125,43216,62232,111398,
%T 115264,115625,126225,142352,191425,194313,235431,243135,261532,
%U 265421,632613,726313,852125,962312,1142536,1148316,1156324,1162825,1183491,1671183,1672125,1815912,1831525,1914157,2124535,2228224,2321375,2364132,2463312,3356122,3416541,3541252,3716118,3741812,4128831,4218912,4331236,4522136,5148512,5181293,5183219,5463161,6219612,6288113,6411925,6811922,7452313,7518119,8741341,9115625,9324222
%N Numbers n such that phi(n)=p^2, where p is product of digits of n.
%H Max Alekseyev, <a href="/A153427/b153427.txt">Table of n, a(n) for n = 1..649</a>
%e phi(2228224)=(2*2*2*8*2*2*4)^2, so 2228224 is in the sequence.
%t Do[If[Apply[Times,IntegerDigits[n]]^2==EulerPhi[n],Print[n]],{n,1200000}]
%t Select[Range[94*10^5],EulerPhi[#]==(Times@@IntegerDigits[#])^2&] (* _Harvey P. Dale_, May 03 2020 *)
%Y Cf. A068572, A153428.
%K base,nonn
%O 1,2
%A _Farideh Firoozbakht_, Jan 02 2009
%E a(33)-a(649) from _Max Alekseyev_, Aug 18 2013, May 31 2018
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