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 A241793 Least number k such that k^n and k^n-1 contain the same number of prime factors (counted with multiplicity) or 0 if no such k exists. 1
 3, 34, 5, 15, 17, 55, 79, 5, 53, 23, 337, 13, 601, 79, 241, 41, 18433, 31, 40961, 89, 3313, 1153 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS a(23) > 3250. a(24) = 79. - Jacques Tramu, Sep 16 2018 100000 < a(23) <= 286721. - Jon E. Schoenfield, Sep 25 2018 LINKS Table of n, a(n) for n=1..22. EXAMPLE 2^1 (2) and 2^1-1 (1) do not have the same number of prime factors. 3^1 (3) and 3^1-1 (2) have the same number of prime factors. Thus a(1) = 3. PROG (PARI) a(n)=for(k=2, oo, if(bigomega(k^n)==bigomega(k^n-1), return(k))); CROSSREFS Cf. A001222 (bigomega), A242786. Sequence in context: A134477 A080985 A006854 * A225427 A037103 A197220 Adjacent sequences: A241790 A241791 A241792 * A241794 A241795 A241796 KEYWORD nonn,more,hard AUTHOR Derek Orr, May 23 2014 EXTENSIONS a(17) and a(19) corrected by Jacques Tramu, Sep 16 2018 STATUS approved

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Last modified June 5 03:52 EDT 2023. Contains 363130 sequences. (Running on oeis4.)