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%I #37 Dec 04 2018 16:31:35
%S 1550860550,44257207676,66072609790
%N Primitive weird numbers (A002975) having 6 distinct prime factors.
%C a(4) <= 5976833582079328 = 2^5*181*197*353*431*34429 and a(5) <= 48083019473926272314825065088 = 2^7*257*97213*97973*100957*1520132521 that is certainly in this sequence. - _Giuseppe Melfi_, Oct 26 2015
%C a(4) <= 125258675788784 = 2^4 * 47 * 149 * 353 * 1307 * 2423. - _M. F. Hasler_, Jul 12 2016
%H G. Amato, M. Hasler, G. Melfi and M. Parton, <a href="http://rivista.math.unipr.it/vols/2016-7-1/amato-et-al.html">Primitive weird numbers having more than three distinct prime factors</a>, Riv. Mat. Univ. Parma, Vol. 7, No. 1 (2016) 153-163.
%H G. Melfi, <a href="http://dx.doi.org/10.1016/j.jnt.2014.07.024">On the conditional infiniteness of primitive weird numbers</a>, Journal of Number Theory, 147 (2015) 508-514; Lemma 2.
%e a(1) = 1550860550 = 2 * 5^2 * 29 * 37 * 137 * 211 = A273815(1). (Abundance = 20)
%e a(2) = 44257207676 = 2^2 * 11 * 37 * 59 * 523 * 881. (Abundance = 8, cf. A088833)
%e a(3) = 66072609790 = 2 * 5 * 11 * 127^2 * 167 * 223 = A273815(3). (Abundance = 4, cf. A088832)
%t (* copy the terms from A002975, assign them to 'lst' and then *)
%t Select[ lst, PrimeNu@# == 6 &]
%o (PARI) select(w->omega(w)==6, A002975) \\ Assuming that A002975 is defined as set or vector. - _M. F. Hasler, Jul 12 2016_
%Y Cf. A002975, A258401, A258882, A258883, A258884.
%K nonn,bref,hard,more
%O 1,1
%A _Douglas E. Iannucci_ and _Robert G. Wilson v_, Jun 14 2015
%E One more term added and definition corrected by _Giuseppe Melfi_, Nov 02 2015