A179012 Primes that are the sum of three consecutive composite odd numbers.

61, 73, 107, 163, 197, 233, 263, 271, 331, 397, 409, 419, 467, 523, 571, 599, 677, 691, 757, 827, 839, 883, 929, 997, 1039, 1051, 1063, 1097, 1123, 1153, 1163, 1171, 1187, 1223, 1231, 1291, 1301, 1367, 1433, 1493, 1523, 1531, 1571, 1619, 1627, 1637, 1667, 1693, 1783

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

Cf. A034962, A034965, A082246, A179007.

Sequence in context: A039478 A109549 A139944 * A227980 A364662 A227520

Adjacent sequences: A179009 A179010 A179011 * A179013 A179014 A179015

Keyword

nonn

Author

Vladimir Joseph Stephan Orlovsky, Jan 07 2011

Status

approved