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%I #18 Feb 14 2019 01:56:00
%S 2,3,5,7,29,67,89,199,599,2999,4999,29989,59999,79999,389999,989999,
%T 6999899,8989999,59899999,89999999,289999999,799999999,3999998999,
%U 19999997999,79999999999,399999998999,599999899999,999998999999
%N Smallest prime number whose digits sum to n-th prime.
%C a(n) >= A051885(A000040(n)). Indices n for which the equality holds are listed in A055019.
%C a(n) >= A046864(n). - _Michel Marcus_, Nov 01 2015
%H Chris Caldwell and G. L. Honaker, Jr., <a href="https://primes.utm.edu/curios/page.php?curio_id=18526">Prime curio for 8999</a>
%e E.g. a(7)=89 because 8+9=17 and 17 is the 7th prime.
%o (PARI) a(n) = {my(k=2); my(p=prime(n)); while((sumdigits(k) != prime(n)), k=nextprime(k+1)); k;} \\ _Michel Marcus_, Nov 01 2015
%Y Cf. A000040, A067180, A046704, A046704, A046864, A068951, A007605.
%K base,nonn
%O 1,1
%A _G. L. Honaker, Jr._, Apr 24 2000
%E More terms from Kok Seng Chua (chuaks(AT)ihpc.nus.edu.sg), May 31 2000
%E Edited and extended by _Robert G. Wilson v_, Feb 26 2002
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