OFFSET
1,1
COMMENTS
Primes of the form 3*k^2 + 18*k + 35 = 3*(k+3)^2 + 8, k >= 0. - R. J. Mathar, Apr 06 2009
Primes which are the sum of 3 consecutive odd squares A016754. - Alex Ratushnyak, Jul 24 2012
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..5000
EXAMPLE
MATHEMATICA
tr[a_]:=Module[{x}, s=0; If[a<0, b=Abs[a]+1, b=a]; For[i=1, i<b, s+=i; i++ ]; x=s]; lst={}; Do[a1=tr[n]; b1=tr[n+1]; c1=tr[n+2]; d1=tr[n+3]; e1=tr[n+4]; f1=tr[n+5]; p=a1+b1+c1+d1+e1+f1; If[PrimeQ[p], AppendTo[lst, p]], {n, -2, 6!}]; lst
Select[Table[3n^2+8, {n, 2, 1000}], PrimeQ] (* Vincenzo Librandi, Dec 02 2011 *)
PROG
(Magma) [a: n in [2..400] | IsPrime(a) where a is 3*n^2+8]; // Vincenzo Librandi, Dec 02 2011
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Vladimir Joseph Stephan Orlovsky, Apr 04 2009
EXTENSIONS
11 removed, examples edited by R. J. Mathar, Apr 06 2009
STATUS
approved