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%I #19 Oct 15 2017 21:55:32
%S 11,211,33211,44433211,5544433211,65544433211,77777777777765544433211
%N a(1) = 11, a(n) = smallest prime obtained by starting with a(n-1) and prefixing it with one or more copies of (the decimal expansion of) n.
%C Next term has 657 digits and is too large to include. - _David Wasserman_, Jul 01 2005
%C a(9) has 1280 digits: 623 repeats of "9" + 634 repeats of "8" + 12 repeats of "7" + "65544433211". a(10) has 4990 digits: 1855 repeats of "10" + a(9). a(8), a(9), a(10) are verified by PARI ispseudoprime function. - _Dmitry Petukhov_, Oct 15 2017
%e a(3) = 33211 as 3211 is not a prime but 33211 is.
%o (PARI) x=0; n=-1; for(k=1, 9, z=n; while(1, n++; x=x+k*10^n; if(ispseudoprime(x), print(x); break))) \\ _Dmitry Petukhov_, Oct 15 2017
%Y Cf. A088062.
%K base,nonn
%O 1,1
%A _Amarnath Murthy_, Sep 21 2003