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%I #5 Dec 05 2013 19:56:20
%S 1,23,307,4489,50021,600007,7000003,80062991,900660121,1000000006,
%T 11000000021,120000000004,1300000000021,14000000000001,
%U 150000000000017,1604502443050081,17000000000000009,180000000000000027
%N Smallest n-digit number beginning with n and having prime signature of n, or 0 if no such number exists.
%C Conjecture: no term is zero.
%e a(4) = 4489 = 67^2, 4= 2^2. a(12) = 120000000004= 2^2*30000000001, prime signature: p^2*q.
%K base,nonn
%O 1,2
%A _Amarnath Murthy_, Aug 30 2003
%E Corrected and extended by _Sascha Kurz_, Sep 22 2003