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A134598
Duplicate of A080773.
0
1, 2, 2, 2, 3, 3, 3, 4, 3, 3, 4, 3, 4, 4, 4, 2, 5, 3, 4, 5, 4, 4, 5, 4, 4, 6, 5, 4, 5, 5, 5, 5, 3, 5, 6, 3, 4, 5, 5, 3, 6, 4, 5, 6, 5, 5, 6, 6, 5, 4, 5, 4, 7, 5, 6, 5, 5, 5, 6, 5, 6, 7, 6, 5, 6, 3, 4, 6, 6, 4, 7, 3, 4, 6, 5, 6, 6, 5, 6, 8, 4, 4, 7, 4, 5, 6, 6, 4, 7, 6, 6, 7, 6, 5, 7, 3, 7, 7, 6, 4, 5, 5, 6, 7, 5
OFFSET
2,2
FORMULA
If p_1*p_2*p_3* ... *p_m=n is the unique prime factorization of n, then a(n)=sum{1<=k<=m, ds_2(p_k)}, where ds_2 is the digital sum base 2.
EXAMPLE
a(6)=3, since 6=2*3 and so a(6)=ds_2(2)+ds_2(3)=1+2.
CROSSREFS
Sequence in context: A259529 A196052 A080773 * A325120 A064515 A112754
KEYWORD
dead
AUTHOR
Hieronymus Fischer, Nov 11 2007
STATUS
approved