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

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

Offset: 1

Author

Joseph L. Pe, Jan 28 2004

Keywords

• nonn

Comments

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]

Programs

Mathematica

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 *)