OFFSET
1,3
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..10000
FORMULA
a(n) = (A142313(n)-47)/90.
MAPLE
for n from 0 to 240 do
p := 90*n+47 ;
if isprime(p) then
printf("%d, ", n) ;
end if;
end do: # R. J. Mathar, Dec 05 2011
MATHEMATICA
Select[Range[0, 400], PrimeQ[90 #+47]&] (* Vincenzo Librandi, Dec 11 2011 *)
PROG
(Magma) [n: n in [0..200] | IsPrime(90*n+47)]; // Vincenzo Librandi, Dec 11 2011
(PARI) is(n)=isprime(90*n+47) \\ Charles R Greathouse IV, Feb 17 2017
CROSSREFS
KEYWORD
nonn,easy,less
AUTHOR
J. W. Helkenberg, Dec 04 2011
STATUS
approved