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%I #9 Apr 11 2023 04:17:46
%S 2,0,6,10,20,31,47,53,65,77,89,113,125,119,149,173,167,179,233,279,
%T 239,209,439,293,365,299,329,359,455,521,467,389,461,419,479,773,539,
%U 509,599,845,671,791,749,719,659,629,809,1055,881,779,899,965,929,1121,839,1403
%N a(n) is the least number k such that the equation A323410(x) = k has exactly n solutions, or -1 if no such k exists.
%C Is there any n for which a(n) = -1?
%H Amiram Eldar, <a href="/A362186/b362186.txt">Table of n, a(n) for n = 0..1292</a>
%F A362181(a(n)) = n.
%t ucototient[n_] := n - Times @@ (Power @@@ FactorInteger[n] - 1); ucototient[1] = 0; With[{max = 300}, solnum = Table[0, {n, 1, max}]; Do[If[(i = ucototient[k]) <= max, solnum[[i]]++], {k, 2, max^2}]; Join[{2, 0}, TakeWhile[FirstPosition[ solnum, #] & /@ Range[2, max] // Flatten, NumberQ]]]
%Y The unitary version of A063507.
%Y Cf. A323410, A362181.
%Y Similar sequences: A007374, A361970.
%K nonn
%O 0,1
%A _Amiram Eldar_, Apr 10 2023
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