OFFSET
1,1
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
EXAMPLE
15+21+25=61, 21+25+27=73, 33+35+39=107.
MATHEMATICA
lst={}; Do[If[!PrimeQ[n], s=n; k=1, Continue[]]; If[!PrimeQ[n+2], s+=n+2; k=2; q=2, If[!PrimeQ[n+4], s+=n+4; k=2; q=4, If[!PrimeQ[n+6], s+=n+6; k=2; q=6]]]; If[!PrimeQ[n+q+2], s+=n+q+2; k=3; q+=2, If[!PrimeQ[n+q+4], s+=n+q+4; k=3; q+=4, If[!PrimeQ[n+q+6], s+=n+q+6; k=3; q+=6]]]; If[PrimeQ[s], AppendTo[lst, s]], {n, 9, 6!, 2}]; lst
nn=1001; With[{compodd=Complement[Range[9, nn, 2], Prime[Range[ PrimePi[ nn]]]]}, Select[ Total/@ Partition[compodd, 3, 1], PrimeQ]] (* Harvey P. Dale, Dec 09 2012 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Vladimir Joseph Stephan Orlovsky, Jan 07 2011
STATUS
approved