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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.
4
6, 10, 12, 15, 14, 20, 21, 18, 24, 28, 35, 22, 36, 40, 33, 45, 26, 44, 56, 39, 55, 63, 52, 72, 65, 77, 34, 48, 88, 51, 91, 99, 38, 68, 80, 104, 57, 85, 117, 30, 76, 112, 95, 119, 143, 46, 136, 144, 69, 133, 153, 50, 92, 152, 176, 75, 115, 171, 187, 54, 100, 208
OFFSET
2,1
COMMENTS
The offset is 2 since A323410(p) = 1 for all prime powers p (A246655).
The 0th row consists of one term, 1, since 1 is the only solution to A323410(x) = 0.
LINKS
Amiram Eldar, Table of n, a(n) for n = 2..12684 (rows 2..1000)
EXAMPLE
The table begins:
n n-th row
-- -----------
2
3
4 6;
5
6 10, 12;
7 15;
8 14, 20;
9 21;
10 18, 24, 28;
11 35;
12 22, 36, 40;
MATHEMATICA
ucototient[n_] := n - Times @@ (Power @@@ FactorInteger[n] - 1); ucototient[1] = 0;
With[{max = 28}, ucot = Table[ucototient[n], {n, 1, max^2}]; row[n_] := Position[ucot, n] // Flatten; Table[row[n], {n, 2, max}] // Flatten]
CROSSREFS
Cf. A246655, A323410, A362181 (row lengths).
Similar sequences: A032447, A361966, A362213.
Sequence in context: A355791 A108315 A134616 * A081390 A210578 A274426
KEYWORD
nonn,tabf
AUTHOR
Amiram Eldar, Apr 10 2023
STATUS
approved