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A302299 Values of A000010(m) such that no solutions share the same prime signature. 1

%I

%S 1,2,4,6,8,10,16,18,22,28,30,32,42,44,46,52,54,56,58,64,66,70,78,82,

%T 92,100,102,104,106,110,116,126,128,130,136,138,140,148,150,162,164,

%U 166,172,178,184,190,196,198,204,208,210,212,220,222,226,228,238,250,256,260

%N Values of A000010(m) such that no solutions share the same prime signature.

%H Max Alekseyev, <a href="http://home.gwu.edu/~maxal/gpscripts/">PARI scripts for various problems</a> (see invphi.gp there).

%e 1 is a term as the only solutions A000010(1) and A000010(2) do not share the same prime signature.

%e 2 is a term as the only solutions A000010(3), A000010(4), and A000010(6) do not share the same prime signature.

%e 12 is not a term since A000010(21) = A000010(26) are solutions and the prime signature of 21 and 26 is {1,1}.

%o (PARI) signa(n) = {my(f = factor(n)); vecsort(f[,2]);}

%o isok(n) = {my(vinv = invphi(n), vinvs = vector(#vinv, k, signa(vinv[k]))); return (#vinvs == #Set(vinvs));}

%o lista(nn) = {for (n=1, nn, if (istotient(n) && isok(n), print1(n, ", ")););} \\ _Michel Marcus_, Apr 08 2018

%Y Complement of A302297 w.r.t. A002202. Cf. A000010.

%K nonn

%O 1,2

%A _Torlach Rush_, Apr 04 2018

%E More terms from _Michel Marcus_, Apr 09 2018

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Last modified June 24 04:50 EDT 2021. Contains 345416 sequences. (Running on oeis4.)