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Primes p+10^n arising in A127003.
1

%I #7 Dec 30 2024 12:54:19

%S 3,13,103,1013,10007,100003,1000003,10000019,100000007,1000000007,

%T 10000000019,100000000003,1000000000061,10000000000037,

%U 100000000000031,1000000000000037,10000000000000061,100000000000000003,1000000000000000003,10000000000000000097

%N Primes p+10^n arising in A127003.

%C Equivalently, smallest prime q such that q-10^n is also prime.

%t s={}; Do[p=0; Until[PrimeQ[q=Prime[p]+10^n], p++]; AppendTo[s, q], {n, 0,20}]; s (* _James C. McMahon_, Dec 30 2024 *)

%Y Cf. A127003, A056208.

%K nonn

%O 1,1

%A _Rick L. Shepherd_, Jan 01 2007

%E a(18)-a(19) from _James C. McMahon_, Dec 30 2024