

A168080


Numbers n such that exactly two of n+1, n+2 and n+3 are primes.


1



0, 1, 2, 3, 9, 12, 15, 18, 21, 22, 26, 28, 30, 32, 34, 38, 39, 42, 45, 46, 50, 56, 58, 60, 62, 64, 68, 69, 72, 74, 76, 80, 81, 82, 86, 98, 99, 102, 105, 108, 111, 112, 128, 129, 130, 134, 136, 138, 140, 148, 150, 152, 154, 160, 164, 165, 166, 170, 176, 178, 180, 182
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,3


LINKS

G. C. Greubel, Table of n, a(n) for n = 1..1000


MATHEMATICA

okQ[n_]:=Length[Select[Drop[Range[n3, n+3], {4}], PrimeQ]]==2; Join[{0, 1}, Select[Range[0, 200], okQ]] (* Harvey P. Dale, Jun 29 2011 *)


CROSSREFS

Cf. A000040, A100317.
Sequence in context: A088086 A088084 A182203 * A048084 A067719 A057017
Adjacent sequences: A168077 A168078 A168079 * A168081 A168082 A168083


KEYWORD

nonn


AUTHOR

JuriStepan Gerasimov, Nov 18 2009


EXTENSIONS

Corrected (14 removed, 58, 62, 74 inserted, etc.) by R. J. Mathar, Jun 04 2010


STATUS

approved



