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%I #6 Mar 24 2021 05:58:43
%S 0,73,0,0,77711,77713,7717,719,7723,77777777777777777729,77731,777737,
%T 7741,743,77747,7753,7759,761,77777777767,7777777777771,773,
%U 777777777777777777777777777777777777777777777777777777777777777779
%N Smallest prime of the form: all sevens followed by prime(n); a(n) > prime(n); or 0 if no such prime exists.
%C Prime(n) is all zeros followed by prime(n).This is all sevens followed by prime(n). Conjecture: a(n) is nonzero if n >4.
%C The conjecture has been verified for n<100. - Joshua Albert (jba138(AT)psu.edu), Jan 20 2006
%e a(9) = 7723, as 723 is composite, prime(9) = 23.
%t Join[{0,73,0,0},Flatten[Select[#,PrimeQ,1]&/@Table[FromDigits[ PadLeft[ IntegerDigits[n],i,7]],{n,Prime[Range[5,30]]},{i,IntegerLength[ n]+1, 100}]]] (* _Harvey P. Dale_, Nov 20 2013 *)
%Y Cf. A113884, A114785, A113886, A113887, A085074.
%K base,nonn
%O 1,2
%A _Amarnath Murthy_, Nov 18 2005
%E More terms from Joshua Albert (jba138(AT)psu.edu), Jan 20 2006