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A075544 Primes which are the sum of the digital root of the first n primes for some n. 2
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, 857, 919, 941, 947, 953, 967, 997, 1019, 1021, 1061, 1093, 1123, 1153, 1231, 1249, 1381, 1409, 1459 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

MATHEMATICA

s = 0; Do[s = s + Mod[ Prime[n], 9]; If[ PrimeQ[s], Print[s]], {n, 1, 350} ]

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: A057282 A123364 A025553 * A104247 A205511 A095287

Adjacent sequences:  A075541 A075542 A075543 * A075545 A075546 A075547

KEYWORD

nonn,base

AUTHOR

Jon Perry (perry(AT)globalnet.co.uk), Oct 11 2002

EXTENSIONS

Edited by Robert G. Wilson v (rgwv(AT)rgwv.com), Oct 14 2002

Definition corrected by M. F. Hasler, Apr 04 2007

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Last modified February 14 20:38 EST 2012. Contains 205663 sequences.