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 A075544 Primes which are the sum of the digital root of the first n primes for some n. 3
 2, 5, 17, 19, 23, 31, 37, 43, 71, 163, 179, 199, 263, 269, 347, 379, 389, 443, 467, 487, 499, 569, 601, 641, 643, 647, 683, 691, 709, 769, 821, 829, 857, 859, 919, 941, 947, 953, 967, 997, 1019, 1021, 1061, 1093, 1123, 1153, 1231, 1249, 1381, 1409, 1459 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Harvey P. Dale, Table of n, a(n) for n = 1..1000 MATHEMATICA s = 0; Do[s = s + Mod[ Prime[n], 9]; If[ PrimeQ[s], Print[s]], {n, 1, 350} ] Select[Accumulate[Mod[Prime[Range[1000]], 9]], PrimeQ] (* Harvey P. Dale, May 04 2012 *) PROG (PARI) sumdigits2(n)=local(c); while (n>9, c=0; while (n>0, c=c+n%10; n=n-n%10; n=n/10); n=c); n c=0; forprime (p=2, 1000, c=c+sumdigits2(p); if (isprime(c), print1(c, ", "))) CROSSREFS Cf. A010888, A104247. Sequence in context: A123364 A247857 A025553 * A104247 A215425 A205511 Adjacent sequences:  A075541 A075542 A075543 * A075545 A075546 A075547 KEYWORD nonn,base AUTHOR Jon Perry, Oct 11 2002 EXTENSIONS Edited by Robert G. Wilson v, Oct 14 2002 Definition corrected by M. F. Hasler, Apr 04 2007 Corrected by Harvey P. Dale, May 04 2012 STATUS approved

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Last modified January 17 14:12 EST 2019. Contains 319225 sequences. (Running on oeis4.)