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 A090335 Smallest number with exactly n distinct prime factors such that in binary representation the divisors >1 form a prefix code. 2
 1, 2, 33, 2093, 239723, 29918977, 17597346187, 17155385292853, 10633323942990239, 15790705299133143889 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(n) = Min{k: A090330(k)=0 and A001221(k)=n}; Conjecture: the sequence is defined for all n. a(10) <= 281594003343201014885689. - David Wasserman, Dec 13 2005 LINKS EXAMPLE a(3) = 2093 = 7*13*23 with divisors >1: 7, 13, 23, 91, 161, 299 and 2093, which are prefix-free in binary: 111, 1101, 10111, 1011011, 10100001, 100101011 and 100000101101. CROSSREFS Cf. A088862, A090332. Sequence in context: A242621 A206385 A263052 * A302452 A113105 A132567 Adjacent sequences:  A090332 A090333 A090334 * A090336 A090337 A090338 KEYWORD nonn AUTHOR Reinhard Zumkeller, Nov 26 2003 EXTENSIONS More terms from David Wasserman, Dec 13 2005 STATUS approved

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Last modified January 17 20:36 EST 2020. Contains 330987 sequences. (Running on oeis4.)