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 A090346 Number of divisors of prime(n) + prime(n+1). 0

%I

%S 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,

%T 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,

%U 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

%N Number of divisors of prime(n) + prime(n+1).

%C 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]

%t d[i_] := DivisorSigma[0, Prime[i] + Prime[i + 1]]; Table[d[i], {i, 1, 100}]

%t DivisorSigma[0,#]&/@(Total/@Partition[Prime[Range[90]],2,1]) (* _Harvey P. Dale_, Mar 03 2023 *)

%K nonn

%O 1,1

%A _Joseph L. Pe_, Jan 28 2004

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Last modified March 29 10:22 EDT 2023. Contains 361598 sequences. (Running on oeis4.)