OFFSET
2,1
COMMENTS
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
KEYWORD
nonn,tabf
AUTHOR
Amiram Eldar, Apr 10 2023
STATUS
approved