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A321505
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Numbers k such that k and k+1 each have at least 5 distinct prime factors.
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6
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254540, 310155, 378014, 421134, 432795, 483405, 486590, 486794, 488565, 489345, 507129, 522444, 545258, 549185, 558789, 558830, 567644, 577940, 584154, 591260, 598689, 627095, 634809, 637329, 663585, 666995, 667029, 678755, 687939, 690234, 707420, 712425, 720005, 720290, 728364, 743589
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OFFSET
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1,1
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COMMENTS
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LINKS
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MATHEMATICA
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Select[Range[750000], PrimeNu[#] > 4 && PrimeNu[# + 1] > 4 &] (* Amiram Eldar, Nov 12 2018 *)
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PROG
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(PARI) is(n)=omega(n)>=5&&omega(n+1)>=5
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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