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 A065116 Numbers n such that sigma(n) +- tau(n) are primes. 1
 8, 162, 512, 32768, 41472, 3748322, 5120000, 6837602, 8000000, 35701250, 75031250, 78125000, 91125000, 907039232, 10660336128, 11911961250, 21234895362, 41265473762, 55965865922, 209642370242, 835707290112, 1148179179938, 1821331173888, 2097152000000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Intersection of A064205 and A065061. LINKS Donovan Johnson, Table of n, a(n) for n = 1..250 MATHEMATICA Do[ds1 = DivisorSigma[1, n]; ds0 = DivisorSigma[0, n]; If[ PrimeQ[ds1 + ds0] && PrimeQ[ds1 - ds0], Print[n]], {n, 1, 10^7} ] CROSSREFS Cf. A064205, A065061. Sequence in context: A305524 A326099 A171461 * A240410 A061250 A183813 Adjacent sequences:  A065113 A065114 A065115 * A065117 A065118 A065119 KEYWORD nonn AUTHOR Robert G. Wilson v, Nov 12 2001 EXTENSIONS a(10)-a(19) from Donovan Johnson, Jul 09 2010 a(20)-a(24) from Donovan Johnson, Aug 23 2013 STATUS approved

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Last modified October 21 14:20 EDT 2019. Contains 328301 sequences. (Running on oeis4.)