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 A077808 Number of prime factors of numbers containing in their decimal representation only the digits 0 and 1 (counted with multiplicity). 1
 0, 2, 1, 4, 1, 3, 2, 6, 3, 3, 2, 5, 2, 4, 2, 8, 2, 5, 3, 5, 4, 4, 1, 7, 3, 4, 4, 6, 2, 4, 2, 10, 2, 4, 4, 7, 3, 5, 3, 7, 3, 6, 2, 6, 4, 3, 1, 9, 3, 5, 3, 6, 2, 6, 2, 8, 2, 4, 2, 6, 2, 4, 5, 12, 2, 4, 2, 6, 2, 6, 2, 9, 2, 5, 4, 7, 2, 5, 2, 9, 2, 5, 3, 8, 3, 4, 2, 8, 1, 6, 3, 5, 4, 3, 4, 11, 5, 5, 3, 7, 1, 5 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS FORMULA a(n) = A001222(A007088(n)). EXAMPLE a(36) = A001222(A007088(36)) = A001222(100100) = A001222(2*2*5*5*7*11*13) = 7. MATHEMATICA PrimeOmega[#]&/@(Rest[Union[Flatten[Table[FromDigits/@Tuples[ {0, 1}, n], {n, 7}]]]]) Harvey P. Dale, May 18 2012 CROSSREFS Cf. A077807. Sequence in context: A113901 A062799 A063647 * A021471 A088372 A216223 Adjacent sequences:  A077805 A077806 A077807 * A077809 A077810 A077811 KEYWORD nonn,base AUTHOR Reinhard Zumkeller, Nov 16 2002 STATUS approved

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