OFFSET
1,1
COMMENTS
Row sums give A001037.
LINKS
Alois P. Heinz, Rows n = 1..71, flattened
EXAMPLE
MATHEMATICA
Prepend[Table[Map[EulerPhi[#]/n &, Complement[Divisors[2^n - 1], Union[Flatten[Table[Divisors[2^k - 1], {k, 1, n - 1}]]]]], {n, 2, 20}], {2}] // Grid (* Geoffrey Critzer, Dec 02 2019 *)
CROSSREFS
KEYWORD
easy,nonn,tabf
AUTHOR
Vladeta Jovovic, Feb 09 2001
STATUS
approved