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A361967
Number of numbers k such that uphi(k) = n, where uphi is the unitary totient function (A047994).
9
2, 2, 1, 2, 0, 3, 1, 4, 0, 2, 0, 5, 0, 1, 1, 2, 0, 3, 0, 2, 0, 2, 0, 8, 0, 2, 0, 3, 0, 4, 1, 4, 0, 0, 0, 6, 0, 0, 0, 4, 0, 3, 0, 2, 0, 2, 0, 11, 0, 0, 0, 2, 0, 1, 0, 4, 0, 2, 0, 8, 0, 1, 1, 2, 0, 3, 0, 0, 0, 3, 0, 11, 0, 0, 0, 0, 0, 3, 0, 8, 0, 2, 0, 5, 0, 0, 0
OFFSET
1,1
LINKS
FORMULA
a(A347771(n)) = 0.
a(A361969(n)) = 1.
a(A361970(n)) = n.
MATHEMATICA
a[n_] := Length[invUPhi[n]]; Array[a, 100] (* using the function invUPhi from A361966 *)
CROSSREFS
Row lengths of A361966.
The unitary version of A014197.
Cf. A047994, A135347, A347771 (positions of 0's), A361966, A361968 (indices of records), A361969 (positions of 1's), A361970, A361971 (record values).
Sequence in context: A203398 A339275 A225064 * A130071 A321373 A305615
KEYWORD
nonn
AUTHOR
Amiram Eldar, Apr 01 2023
STATUS
approved