OFFSET
1,1
COMMENTS
Primes (excluding 3) ending in 3 with (SOD-1)/3 non-integer where SOD is sum of digits. - Ki Punches
The sequence is infinite by Dirichlet's theorem. - Arkadiusz Wesolowski, Apr 02 2014
Terms are non-twin primes A007510. - Omar E. Pol, Jul 25 2019
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..1000
C. K. Caldwell, The Prime Pages.
Omar E. Pol, Prime numbers in a sieve with 30 columns
FORMULA
a(n) = A158791(n)*30 + 23. - Ray Chandler, Apr 07 2009
MATHEMATICA
Select[Prime[Range[1000]], MemberQ[{23}, Mod[#, 30]]&] (* Vincenzo Librandi, Aug 14 2012 *)
Select[Range[23, 2400, 30], PrimeQ] (* Harvey P. Dale, Jan 27 2020 *)
PROG
(Magma) [p: p in PrimesUpTo(3000) | p mod 30 eq 23 ]; // Vincenzo Librandi, Aug 14 2012
(PARI) is(n)=isprime(n) && n%30==23 \\ Charles R Greathouse IV, Jul 01 2016
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Omar E. Pol, Aug 15 2007
EXTENSIONS
Extended by Ray Chandler, Apr 07 2009
STATUS
approved