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Unitary totient superdeficient numbers: numbers n > 1 such that s(n)/n < s(m)/m for all m < n, where s is the sum of iterated uphi (A047994).
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%I #8 Aug 31 2017 17:44:05

%S 2,3,6,12,14,26,30,42,186,210,2310,66990,903210,1037190,1138830

%N Unitary totient superdeficient numbers: numbers n > 1 such that s(n)/n < s(m)/m for all m < n, where s is the sum of iterated uphi (A047994).

%C The unitary version of A291173.

%t uphi[n_] := If[n == 1, 1, (Times @@ (Table[#[[1]]^#[[2]] - 1, {1}] & /@ FactorInteger[n]))[[1]]]; Function[s, Flatten[First@Position[s, #] & /@ Union@Rest@FoldList[Max, 0, s]]]@ Table[n/(Total@FixedPointList[uphi, n] - (n-5)), {n, 2, 10^4}]+1 (* after _Michael De Vlieger_ at A286268 and _Alonso del Arte_ at A092693 *)

%Y Cf. A047994, A291173.

%K nonn,more

%O 1,1

%A _Amiram Eldar_, Aug 19 2017