OFFSET
1,1
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..1000
EXAMPLE
a(1) = 2+3+5 = 10.
a(2) = 3+5+7 = 15.
a(3) = 7+13+19 = 39.
a(4) = 5+13+17 = 35.
a(5) = 11+31+41 = 83.
a(6) = 7+13+19 = 39.
MATHEMATICA
Table[ps = Select[Table[n*k + 1, {k, 100}], PrimeQ, 3]; If[Length[ps] == 3, Total[ps], 0], {n, 100}] (* T. D. Noe, Oct 21 2011 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Omar E. Pol, Sep 03 2011
STATUS
approved