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%I #11 Feb 11 2013 15:45:27
%S 65,603,12208,18803,18841,25207
%N Numbers n such that the leading n digits of n^n in decimal form a prime or a probable prime.
%C Search completed through n=28900. a(1)=65 occurs in A220454, the 65-digit right truncation of 65^65 being the only prime right truncation for 65 and no first right truncation for a smaller number than 65 being 65 or more digits.
%t Select[Range[8, 1000], PrimeQ[FromDigits[Take[IntegerDigits[#^#], #]]] &] (* _T. D. Noe_, Feb 11 2013 *)
%Y Cf. A220453, A220454.
%K nonn,base
%O 1,1
%A _James G. Merickel_, Feb 09 2013