|
|
A003971
|
|
Inverse Möbius transform of A003960.
|
|
1
|
|
|
1, 2, 3, 3, 4, 6, 5, 4, 7, 8, 7, 9, 8, 10, 12, 5, 10, 14, 11, 12, 15, 14, 13, 12, 13, 16, 15, 15, 16, 24, 17, 6, 21, 20, 20, 21, 20, 22, 24, 16, 22, 30, 23, 21, 28, 26, 25, 15, 21, 26, 30, 24, 28, 30, 28, 20, 33, 32, 31, 36, 32, 34, 35, 7, 32, 42, 35, 30, 39, 40, 37, 28, 38, 40
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
LINKS
|
|
|
FORMULA
|
Multiplicative with a(p^e) = e+1 if p = 2; (((p+1)/2)^(e+1) - 1)/((p-1)/2) if p > 2. - David W. Wilson, Sep 01 2001
|
|
MATHEMATICA
|
f[p_, e_] := (((p + 1)/2)^(e + 1) - 1)/((p - 1)/2); f[2, e_] := e + 1; a[1] = 1; a[n_] := Times @@ f @@@ FactorInteger[n]; Array[a, 100] (* Amiram Eldar, Dec 06 2022 *)
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn,easy,mult
|
|
AUTHOR
|
|
|
EXTENSIONS
|
|
|
STATUS
|
approved
|
|
|
|