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%I #8 Feb 02 2020 16:55:59
%S 83,811,8111,839393939,81313131313,8212121212121,83333333,
%T 89191919191919191,8777777777,829292929292929292929,
%U 85151515151515151515151,8313131313131313131313131,811111111111111111111111111,81313131313131313131313131313
%N Smallest prime of the form 8 followed by n copies of k.
%H Harvey P. Dale, <a href="/A112766/b112766.txt">Table of n, a(n) for n = 1..200</a>
%e a(3) = 8111, 8 followed by three copies of 1.
%t SelectFirst[#,PrimeQ]&/@Table[FromDigits[PadRight[{8},IntegerLength[k] n+1,Reverse[IntegerDigits[k]]]],{n,30},{k,9999}] (* _Harvey P. Dale_, Feb 02 2020 *)
%o (PARI) for(n=1,100,np=1;k=1;while(np,s="8";for(i=1,n,s=concat(s,Str(k)));m=eval(s);if(isprime(m),print1(m",");np=0,k++))) - Herman Jamke (hermanjamke(AT)fastmail.fm), May 01 2008
%K base,nonn,dumb
%O 1,1
%A _Amarnath Murthy_, Jan 02 2006
%E More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), May 01 2008
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