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 A098893 Sum of number of prime-factors of all prefixes in decimal representation of n. 0
 0, 1, 1, 2, 1, 2, 1, 3, 2, 2, 1, 3, 1, 2, 2, 4, 1, 3, 1, 4, 3, 3, 2, 5, 3, 3, 4, 4, 2, 4, 2, 6, 3, 3, 3, 5, 2, 3, 3, 6, 3, 5, 3, 5, 5, 4, 3, 7, 4, 4, 3, 4, 2, 5, 3, 5, 3, 3, 2, 6, 3, 4, 5, 8, 4, 5, 3, 5, 4, 4, 2, 6, 2, 3, 4, 4, 3, 4, 2, 8, 7, 5, 4, 7, 5, 5, 5, 7, 4, 6, 4, 5, 4, 4, 4, 8, 3, 5, 5, 6, 3, 5, 3, 6, 5 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS a(n) = if n<10 then Omega(n) else Omega(n) + a(floor(n/10)), where Omega=A001222. LINKS EXAMPLE a(256)=Omega(256)+a(25)=8+Omega(25)+a(2)=8+2+Omega(2)=10+1=11. CROSSREFS Sequence in context: A320888 A296132 A253557 * A302037 A069248 A008481 Adjacent sequences:  A098890 A098891 A098892 * A098894 A098895 A098896 KEYWORD nonn,base AUTHOR Reinhard Zumkeller, Nov 04 2004 STATUS approved

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Last modified December 18 18:34 EST 2018. Contains 318243 sequences. (Running on oeis4.)