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%I #11 Jul 10 2012 10:19:12
%S 1,103654150315463023813006470,207308300630926047626012940,
%T 414616601261852095252025880,518270751577315119065032350,
%U 829233202523704190504051760,982794906694760522078876160,1036541503154630238130064700
%N Numbers n such that n, phi(n) and sigma(n) have same set of prime factors.
%H Michel Marcus, <a href="/A214266/b214266.txt">Table of n, a(n) for n = 1..100</a>
%H Prime Puzzles, <a href="http://www.primepuzzles.net/puzzles/puzz_451.htm">Puzzle 451</a>
%e For n = 207308300630926047626012940 = 2^2*3^4*5*7*11*13^3*17^3*29^2*31^3*37^2*67^2
%e phi(n) = 2^18*3^9*5^2*7*11*13^2*17^2*29*31^2*37*67 and
%e sigma(n) = 2^16*3^6*5^2*7^5*11^2*13^2*17*29*31*37*67^2
%e have the same prime factors.
%Y Cf. A027598, A055744, A081377.
%K nonn,fini
%O 1,2
%A _Michel Marcus_, Jul 09 2012
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