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A048880
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Primes of form pq+2 where p and q are consecutive primes.
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6
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17, 37, 79, 223, 439, 4759, 22501, 32401, 53359, 57601, 60493, 72901, 77839, 95479, 99223, 159199, 164011, 176401, 194479, 239119, 324901, 378223, 416023, 497011, 680623, 756853, 804511, 1115113, 1664101, 1742401, 2223079
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| All terms > 17 are congruent to 1 mod 6. (Zak Seidov)
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LINKS
| T. D. Noe, Table of n, a(n) for n=1..1000
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EXAMPLE
| 487*491+2=239119.
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MAPLE
| with (numtheory): for n from 1 to 1000 do if (tau(ithprime(n)*ithprime(n+1)+2)=2) then print(ithprime(n), ithprime(n+1), ithprime(n)*ithprime(n+1)+2); fi; od;
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MATHEMATICA
| Reap[Do[If[PrimeQ[p=Prime[k]*Prime[k+1]+2], Sow[p]], {k, 1, 430}]][[2, 1]] (* Zak Seidov Dec 03 2010 *)
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CROSSREFS
| Cf. A051507.
Sequence in context: A050952 A200865 A093930 * A075892 A155143 A141886
Adjacent sequences: A048877 A048878 A048879 * A048881 A048882 A048883
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KEYWORD
| easy,nonn
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AUTHOR
| Herman H. Rosenfeld (herm3(AT)pacbell.net)
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EXTENSIONS
| Corrected and extended by Joe DeMaio (jdemaio(AT)kennesaw.edu).
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