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A079131
Primes such that iterated sum-of-digits (A038194) is odd.
3
3, 5, 7, 19, 23, 37, 41, 43, 59, 61, 73, 79, 97, 109, 113, 127, 131, 149, 151, 163, 167, 181, 199, 223, 239, 241, 257, 271, 277, 293, 307, 311, 313, 331, 347, 349, 367, 379, 383, 397, 401, 419, 421, 433, 439, 457, 487, 491, 509, 523, 541, 547, 563, 577, 599
OFFSET
1,1
COMMENTS
Subsequence of primes of A187318. - Michel Marcus, Jun 08 2015
Primes congruent to 1, 3, 5, 7 mod 18. - Robert Israel, Jun 08 2015
LINKS
MAPLE
select(isprime, [3, seq(seq(i*18+j, j=[1, 5, 7]), i=0..100)]); # Robert Israel, Jun 08 2015
MATHEMATICA
Select[Prime[Range[120]], OddQ[Mod[#, 9]] &] (* Bruno Berselli, Aug 31 2012 *)
PROG
(PARI) forprime(p=2, 600, if((p%9)%2==1, print1(p, ", ")))
(Magma) [p: p in PrimesUpTo(600) | p mod 18 in [1, 3, 5, 7]]; // Vincenzo Librandi, Jun 07 2015
(Magma) [a: n in [0..1000] | IsPrime(a) where a is Floor(9*n/5)]; // Vincenzo Librandi, Jun 08 2015
CROSSREFS
KEYWORD
nonn,easy,base
AUTHOR
Klaus Brockhaus, Dec 28 2002
STATUS
approved