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Smallest prime == 1 mod (10^n).
1

%I #6 Dec 05 2013 19:55:19

%S 11,101,3001,70001,700001,22000001,30000001,600000001,6000000001,

%T 30000000001,1900000000001,18000000000001,40000000000001,

%U 3900000000000001,6000000000000001,130000000000000001,3700000000000000001,15000000000000000001,150000000000000000001,600000000000000000001,16000000000000000000001

%N Smallest prime == 1 mod (10^n).

%C a(6) through a(21) have been certified prime with Primo. - _Rick L. Shepherd_, Jun 03 2002

%F a(n) = A121172(n)*10^n + 1. - _Ray Chandler_, Feb 10 2009

%o (PARI) b(n,k) = k*10^n+1 for(n=1,25, k=1; while(!isprime(b(n,k)),k++); print1(b(n,k),","))

%Y Cf. A070846 to A070853.

%K nonn

%O 1,1

%A _Amarnath Murthy_, May 15 2002

%E More terms from _Rick L. Shepherd_, Jun 03 2002