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%I #7 Dec 05 2015 17:08:44
%S 827,2221,42223,4222222223,42222222223,222222222222222221,
%T 822222222222222222227,42222222222222222222222222222223,
%U 8222222222222222222222222222222227,822222222222222222222222222222222222222222222222222222222222227
%N Primes such that the outer 2 digits are n and n-1 and all inner digits are 2, where 0 < n < 9.
%t Sort[Select[Flatten[Table[FromDigits[Join[{n},PadRight[{},i,2],{n-1}]],{n,2,8,2},{i,70}]],PrimeQ]] (* _Harvey P. Dale_, Dec 05 2015 *)
%o (PARI) n10np1(n,d) = { local(x,y,k); for(x=1,n, for(k=1,8, y=10^(x+1)*k+floor(10^x*d/9)*10+k-1; if(isprime(y),print1(y",")) ) ) }
%K easy,nonn,base
%O 1,1
%A _Cino Hilliard_, Jul 11 2005
%E One more term (a(10)) from _Harvey P. Dale_, Dec 05 2015
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