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A090346
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Number of divisors of prime(n) + prime(n+1).
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0
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2, 4, 6, 6, 8, 8, 9, 8, 6, 12, 6, 8, 12, 12, 9, 10, 16, 8, 8, 15, 8, 10, 6, 8, 12, 12, 16, 16, 8, 20, 8, 6, 12, 18, 18, 12, 14, 16, 12, 12, 24, 12, 16, 16, 18, 8, 8, 18, 16, 16, 8, 24, 12, 6, 16, 12, 24, 6, 12, 12, 21, 24, 8, 20, 24, 20, 6, 18, 16, 16, 8, 12, 12, 10, 8, 6, 8, 16, 20, 18
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OFFSET
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1,1
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COMMENTS
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Positions of odd terms (A064397): 7,15,20,61,152,190,293,377,492,558,789,919,942,1768,2343,2429,... [From Zak Seidov, Oct 12 2010]
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LINKS
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MATHEMATICA
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d[i_] := DivisorSigma[0, Prime[i] + Prime[i + 1]]; Table[d[i], {i, 1, 100}]
DivisorSigma[0, #]&/@(Total/@Partition[Prime[Range[90]], 2, 1]) (* Harvey P. Dale, Mar 03 2023 *)
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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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