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%I #21 Jan 12 2020 11:31:11
%S 2,3,4,5,6,7,8,12,15,27,30,40,44,57,117,128,171,236,399,408,510,1623,
%T 3597,3915,4616,4684,7335,10197,10768,14144,32768,39387,76035,77097,
%U 106605,162450,196080,219966,391696
%N Numbers k for which phi(k) + anti-phi(k) = k.
%C Anti-phi(n) (A066452) is the number of numbers coprime to all the anti-divisors of n.
%C See A066272 for definition of anti-divisor.
%H Jon Perry, <a href="https://web.archive.org/web/20060923020029/http://www.users.globalnet.co.uk/~perry/maths/antidivisorother2.htm">Anti-phi function</a> [Wayback Machine link]
%H Jon Perry, <a href="/A066272/a066272a.html">The Anti-divisor</a> [Cached copy]
%H Jon Perry, <a href="/A066272/a066272.html">The Anti-divisor: Even More Anti-Divisors</a> [Cached copy]
%e The anti-divisors of 7 are 1, 2, 3 and 5. Therefore of the integer 1-6, only 1 is coprime to 2, 3 and 5, therefore anti-phi(7)=1. phi(7)=6, therefore anti-phi(7)+phi(7)=7
%Y Cf. A066416, A066417, A058838, A066241, A066272, A066452.
%K nonn,more
%O 1,1
%A _Jon Perry_, Dec 28 2001
%E a(21)-a(34) from _Nathaniel Johnston_, Apr 20 2011
%E a(35)-a(39) from _Amiram Eldar_, Jan 12 2020
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