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A048880 Primes of form pq+2 where p and q are consecutive primes. 12
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; text; internal format)
OFFSET

1,1

COMMENTS

All terms > 17 are congruent to 1 mod 6. (Zak Seidov)

LINKS

T. D. Noe, Table of n, a(n) for n=1..1000

EXAMPLE

487*491+2=239119.

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;

MATHEMATICA

Reap[Do[If[PrimeQ[p=Prime[k]*Prime[k+1]+2], Sow[p]], {k, 1, 430}]][[2, 1]] (* Zak Seidov Dec 03 2010 *)

CROSSREFS

Cf. A051507.

Sequence in context: A200865 A319245 A093930 * A075892 A155143 A261529

Adjacent sequences:  A048877 A048878 A048879 * A048881 A048882 A048883

KEYWORD

easy,nonn

AUTHOR

Herman H. Rosenfeld (herm3(AT)pacbell.net)

EXTENSIONS

Corrected and extended by Joe DeMaio (jdemaio(AT)kennesaw.edu).

STATUS

approved

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Last modified April 23 10:57 EDT 2021. Contains 343204 sequences. (Running on oeis4.)