OFFSET
1,1
COMMENTS
Also primes congruent to 1 (mod 15). - N. J. A. Sloane, Jul 11 2008
Primes ending in 1 with (SOD-1)/3 integer where SOD is sum of digits. - Ki Punches, Feb 04 2009
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..10000
C. K. Caldwell, The Prime Pages.
FORMULA
a(n) = A111175(n)*30 + 1. - Ray Chandler, Apr 07 2009
EXAMPLE
From Muniru A Asiru, Nov 01 2017: (Start)
31 is a prime and 31 = 30*1 + 1;
61 is a prime and 61 = 30*2 + 1;
151 is a prime and 151 = 30*5 + 1;
211 is a prime and 211 = 30*7 + 1;
241 is a prime and 241 = 30*8 + 1;
271 is a prime and 271 = 30*9 + 1.
(End)
MAPLE
select(isprime, [seq(i, i=1..1000, 30)]); # Robert Israel, Jan 19 2016
MATHEMATICA
Select[Range[1, 3000, 30], PrimeQ] (* Vladimir Joseph Stephan Orlovsky, Feb 19 2012 *)
Select[Prime[Range[400]], Mod[#, 30]==1&] (* Harvey P. Dale, May 21 2021 *)
PROG
(PARI) is(n)=isprime(n) && n%30==1 \\ Charles R Greathouse IV, Jul 01 2016
(GAP) A132230 := Filtered(Filtered([1..10^6], n -> n mod 30 = 1), IsPrime); # Muniru A Asiru, Nov 01 2017
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Omar E. Pol, Aug 15 2007
EXTENSIONS
Edited by Ray Chandler, Apr 07 2009
STATUS
approved