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 A078403 Primes such that digital root (A038194) is prime. 10
 2, 3, 5, 7, 11, 23, 29, 41, 43, 47, 59, 61, 79, 83, 97, 101, 113, 131, 137, 149, 151, 167, 173, 191, 223, 227, 239, 241, 257, 263, 277, 281, 293, 311, 313, 317, 331, 347, 349, 353, 367, 383, 389, 401, 419, 421, 439, 443, 457, 461, 479, 491, 509, 547, 563, 569 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS EXAMPLE 59 is a term because 5+9=14, giving (final) iterated sum 1+4=5 and 5 is prime. MATHEMATICA Select[ Range[580], PrimeQ[ # ] && PrimeQ[Mod[ #, 9]] &] Select[Prime[Range[200]], PrimeQ[Mod[#, 9]]&] (* Harvey P. Dale, Aug 20 2017 *) PROG (PARI) forprime(p=2, 997, if(isprime(p%9), print1(p, ", "))) CROSSREFS Cf. A070027, A078400. Sequence in context: A284146 A317479 A087521 * A129945 A046704 A089392 Adjacent sequences:  A078400 A078401 A078402 * A078404 A078405 A078406 KEYWORD base,easy,nonn AUTHOR N. J. A. Sloane, Dec 26 2002 EXTENSIONS Extended by Robert G. Wilson v, Klaus Brockhaus and Rick L. Shepherd, Dec 27 2002 STATUS approved

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Last modified April 10 22:28 EDT 2021. Contains 342856 sequences. (Running on oeis4.)