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%I #5 Jun 01 2020 20:46:13
%S 1,2,6,12,24,72,120,240,480,1440,2880,5760,8640,17280,65280,86400,
%T 120960,130560,259200,391680,783360,1566720,2350080,4700160,23500800,
%U 32901120,47001600,70502400,94003200,470016000,1410048000,2820096000,4294901760,5640192000,8460288000
%N Numbers k such that iphi(k) divides k, where iphi is an infinitary analog of Euler's phi function (A091732).
%e 6 is a term since iphi(6) = 2 is a divisor of 6.
%t f[p_, e_] := p^(2^(-1 + Position[Reverse @ IntegerDigits[e, 2], 1])); a[1] = 1; iphi[n_] := Times @@ (Flatten@(f @@@ FactorInteger[n]) - 1); Select[Range[10^5], Divisible[#,a[#]] &]
%Y Cf. A007694, A091732, A319481.
%K nonn
%O 1,2
%A _Amiram Eldar_, Jun 01 2020
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