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The sum of the n-th and (n+1)st isolated prime.
1

%I #9 Aug 02 2017 05:06:01

%S 25,60,84,100,120,146,162,172,186,210,240,258,288,320,330,340,384,434,

%T 456,484,508,520,540,570,600,624,648,668,690,712,726,740,752,762,772,

%U 786,798,810,848,882,892,906,924,946,966,978,990,1002,1012,1050,1088,1104,1120

%N The sum of the n-th and (n+1)st isolated prime.

%H G. C. Greubel, <a href="/A163654/b163654.txt">Table of n, a(n) for n = 1..1000</a>

%F a(n) = A007510(n) + A007510(n+1).

%e a(1) = 25 = 2+23.

%t A007510 := Select[Prime[Range[4, 2000]], ! PrimeQ[# - 2] && ! PrimeQ[# + 2] &]; Join[{25}, Table[A007510[[n]] + A007510[[n + 1]], {n, 1, 50}]] (* _G. C. Greubel_, Aug 01 2017 *)

%Y Cf. A007510.

%K nonn

%O 1,1

%A _Juri-Stepan Gerasimov_, Aug 02 2009

%E 330 inserted by _R. J. Mathar_, Aug 06 2009