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a(n) = if n<10 then Omega(n) else Omega(n) + a(floor(n/10)), where Omega=A001222.
Table of n, a(n) for n=1..105.
Sequence in context: A001222 A257091 A253557 * A069248 A008481 A127669
Adjacent sequences: A098890 A098891 A098892 * A098894 A098895 A098896
Reinhard Zumkeller, Nov 04 2004