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A063788
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Numbers n such that sigma(n) = 2n + Omega(n), where Omega(n) is the number of prime divisors of n (with repetition).
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0
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OFFSET
| 1,1
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COMMENTS
| a(9) <= 2251798907715584. a(10) <= 633825300114085990300727115776. a(11) <= 2596148429267411760623818083663872. [From Donovan Johnson (donovan.johnson(AT)yahoo.com), Dec 19 2008]
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PROG
| (PARI) for(n=1, 10^8, if(sigma(n)==2*n+bigomega(n), print(n)))
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CROSSREFS
| Sequence in context: A124935 A126405 A141842 * A066854 A059138 A117735
Adjacent sequences: A063785 A063786 A063787 * A063789 A063790 A063791
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KEYWORD
| more,nonn
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AUTHOR
| Jason Earls (zevi_35711(AT)yahoo.com), Aug 16 2001
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EXTENSIONS
| a(7)-a(8) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Dec 19 2008
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