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Smallest prime of the form 10^k + prime(n), k >= d, the number of digits in prime(n). 0 if no such primes exist. a(n) = 0 if prime(n) + 1 == 0 (mod 3).
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%I #5 Dec 05 2013 19:57:14

%S 0,13,0,17,0,113,0,1019,0,0,131,137,0,100043,0,0,0,1061,167,0,173,179,

%T 0,0,197,0,1103,0,1109,0,100000127,0,0,10139,0,1151,

%U 100000000000000000000157,1163,0,0,0,1181,0,1193,0,1000199,10211,1223,0,1229,0,0,1000000241,0,0,0,0,10271,1277,0,1283,0

%N Smallest prime of the form 10^k + prime(n), k >= d, the number of digits in prime(n). 0 if no such primes exist. a(n) = 0 if prime(n) + 1 == 0 (mod 3).

%C Conjecture a(n) = 0 iff prime(n) + 1 == 0 (mod 3).

%e a(8) = 1019 = 19 + 10^3, prime(8) = 19.

%Y Cf. A114780.

%K base,nonn

%O 1,2

%A _Amarnath Murthy_, Nov 17 2005

%E More terms from _Joshua Zucker_, May 06 2006