This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A286067 #13 May 07 2020 05:25:19
%S A286067 3,10,21,110,3910,1500988838
%N A286067 Unitary perfect totient numbers: numbers n that equal to the sum of their iterated unitary totient uphi(n).
%C A286067 The unitary version of A082897 (perfect totient numbers), in which the unitary totient function uphi(n) (A047994) replaces the Euler totient function phi(n) (A000010).
%C A286067 a(7) > 5*10^9, if it exists. - _Giovanni Resta_, May 06 2020
%e A286067 3910 is a unitary perfect totient number because 3910 = uphi(3910) + uphi(uphi(3910)) + uphi(uphi(uphi(3910))) + ... = 1408 + 1270 + 504 + 336 + 180 + 96 + 62 + 30 + 8 + 7 + 6 + 2 + 1.
%t A286067 uphi[n_] := (Times @@ (Table[#[[1]]^#[[2]] - 1, {1}] & /@ FactorInteger[n]))[[1]]; kmax = 10000; a = Table[0, {kmax}]; uptns = {}; Do[e = uphi[k]; a[[k]] = e + a[[e]]; If[k == a[[k]], AppendTo[uptns , k]], {k, 2, kmax}]; uptns
%Y A286067 Cf. A082897, A047994, A003271, A000010.
%K A286067 nonn,more
%O A286067 1,1
%A A286067 _Amiram Eldar_, May 01 2017
%E A286067 a(6) from _Giovanni Resta_, May 06 2020