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A362180 Irregular table read by rows in which the n-th row consists of all the numbers m such that A323410(m) = n.

%I A362180 #11 Apr 11 2023 04:18:11
%S A362180 6,10,12,15,14,20,21,18,24,28,35,22,36,40,33,45,26,44,56,39,55,63,52,
%T A362180 72,65,77,34,48,88,51,91,99,38,68,80,104,57,85,117,30,76,112,95,119,
%U A362180 143,46,136,144,69,133,153,50,92,152,176,75,115,171,187,54,100,208
%N A362180 Irregular table read by rows in which the n-th row consists of all the numbers m such that A323410(m) = n.
%C A362180 The offset is 2 since A323410(p) = 1 for all prime powers p (A246655).
%C A362180 The 0th row consists of one term, 1, since 1 is the only solution to A323410(x) = 0.
%H A362180 Amiram Eldar, <a href="/A362180/b362180.txt">Table of n, a(n) for n = 2..12684</a> (rows 2..1000)
%e A362180 The table begins:
%e A362180   n   n-th row
%e A362180   --  -----------
%e A362180    2
%e A362180    3
%e A362180    4  6;
%e A362180    5
%e A362180    6  10, 12;
%e A362180    7  15;
%e A362180    8  14, 20;
%e A362180    9  21;
%e A362180   10  18, 24, 28;
%e A362180   11  35;
%e A362180   12  22, 36, 40;
%t A362180 ucototient[n_] := n - Times @@ (Power @@@ FactorInteger[n] - 1); ucototient[1] = 0;
%t A362180 With[{max = 28}, ucot = Table[ucototient[n], {n, 1, max^2}]; row[n_] := Position[ucot, n] // Flatten; Table[row[n], {n, 2, max}] // Flatten]
%Y A362180 Cf. A246655, A323410, A362181 (row lengths).
%Y A362180 Similar sequences: A032447, A361966, A362213.
%K A362180 nonn,tabf
%O A362180 2,1
%A A362180 _Amiram Eldar_, Apr 10 2023