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A258885
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Primitive weird numbers (A002975) having 6 distinct prime factors.
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12
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OFFSET
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1,1
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COMMENTS
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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
a(4) <= 125258675788784 = 2^4 * 47 * 149 * 353 * 1307 * 2423. - M. F. Hasler, Jul 12 2016
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LINKS
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EXAMPLE
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a(1) = 1550860550 = 2 * 5^2 * 29 * 37 * 137 * 211 = A273815(1). (Abundance = 20)
a(2) = 44257207676 = 2^2 * 11 * 37 * 59 * 523 * 881. (Abundance = 8, cf. A088833)
a(3) = 66072609790 = 2 * 5 * 11 * 127^2 * 167 * 223 = A273815(3). (Abundance = 4, cf. A088832)
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MATHEMATICA
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(* copy the terms from A002975, assign them to 'lst' and then *)
Select[ lst, PrimeNu@# == 6 &]
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PROG
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(PARI) select(w->omega(w)==6, A002975) \\ Assuming that A002975 is defined as set or vector. - _M. F. Hasler, Jul 12 2016_
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CROSSREFS
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KEYWORD
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nonn,bref,hard,more
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AUTHOR
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EXTENSIONS
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One more term added and definition corrected by Giuseppe Melfi, Nov 02 2015
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STATUS
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approved
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