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 A046460 Number of prime factors of concatenation of numbers from 1 up to n, with multiplicity. 11
 0, 3, 2, 2, 3, 8, 2, 5, 4, 3, 6, 6, 3, 3, 3, 4, 5, 6, 6, 10, 8, 6, 4, 6, 5, 9, 8, 7, 4, 7, 3, 6, 6, 2, 8, 9, 4, 4, 6, 9, 5, 7, 4, 7, 10, 7, 5, 8, 6, 10, 3, 9, 8, 14, 5, 5, 6, 4, 4, 8, 3, 8, 5, 10, 6, 8, 3, 10, 7, 6, 6, 7, 3, 9, 6, 6, 5, 6, 6, 10, 6, 7, 6, 7, 6 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Patrick De Geest, Normal Smarandache Concatenated Numbers, Prime factors from 1 up to n M. Fleuren, Factors and primes of Smarandache sequences. M. Fleuren, Smarandache Factors and Reverse factors Carlos Rivera, Puzzle 8. Primes by Listing, The Prime Puzzles & Problems Connection. MATHEMATICA Join[{1}, Table[PrimeOmega[FromDigits[Flatten[IntegerDigits[Range[i]]]]], {i, 2, 35}]] (* Jayanta Basu, Jun 02 2013 *) PROG (PARI) conc(n) = my(s=""); for(k=1, n, s=Str(s, k)); eval(s); \\ A007908 a(n) = bigomega(conc(n)); \\ Michel Marcus, Oct 16 2019 CROSSREFS Cf. A007908, A046461, A046462, A046463, A046464, A046465, A046466, A046467, A046468, A050677. Sequence in context: A248756 A059942 A032450 * A327661 A117643 A141862 Adjacent sequences:  A046457 A046458 A046459 * A046461 A046462 A046463 KEYWORD nonn,hard,base AUTHOR Patrick De Geest, Aug 15 1998 EXTENSIONS Offset 1 and a(1)=0 from Michel Marcus, Oct 16 2019 More terms from Sean A. Irvine, Apr 10 2021 STATUS approved

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Last modified June 20 23:44 EDT 2021. Contains 345316 sequences. (Running on oeis4.)