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 A258374 Least primitive weird number with n prime divisors, not counting multiplicity. 8
 70, 4030, 4199030, 1550860550 (list; graph; refs; listen; history; text; internal format)
 OFFSET 3,1 COMMENTS A proper subset of A002975. So far all terms are == 2 (mod 4). From M. F. Hasler, Jul 18 2016: (Start) a(3) = 2 * 5 * 7 = A002975(1) = A258882(1), a(4) = 2 * 5 * 13 * 31 = A258401(1) = A258883(1), a(5) = 2 * 5 * 11 * 59 * 647 = A258884(1), a(6) = 2 * 5^2 * 29 * 37 * 137 * 211 = A258885(1) = A273815(1). (End) a(7) <= 4 * 13 * 17 * 449 * 24809 * 228259243 * 11449243661 ≈ 2.6e28, a(8) <= 4 * 13 * 17 * 449 * 24809 * 223842061 * 1123622795959 * 16039588627050434791 ≈ 3.97 e49. - M. F. Hasler, Aug 02 2016 a(7) <= 2 * 5 * 11 * 89 * 167 * 829 * 7972687 ≈ 1.1e16. - M. F. Hasler, Feb 18 2018 LINKS MATHEMATICA (* copy the terms from A002975, assign them equal to 'lst' and then *) Table[ Min@ Select[ lst, PrimeNu@# == n &], {n, 3, 6}] CROSSREFS Cf. A002975, A258375. Sequence in context: A292986 A064114 A319735 * A146349 A180884 A238540 Adjacent sequences:  A258371 A258372 A258373 * A258375 A258376 A258377 KEYWORD nonn,hard,more AUTHOR Robert G. Wilson v, May 28 2015 STATUS approved

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Last modified May 12 07:28 EDT 2021. Contains 343821 sequences. (Running on oeis4.)