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%I #14 Nov 11 2021 10:29:32
%S 11,11,101,1009,10007,100003,1000003,10000019,100000007,1000000007,
%T 10000000019,100000000003,1000000000039,10000000000037,
%U 100000000000031,1000000000000037,10000000000000061,100000000000000003,1000000000000000003,10000000000000000051
%N Smallest prime in which the n-th significant digit is a 1.
%C Essentially (i.e., except for the initial term), the same as A003617. The definition is misleading, since "n-th significant digit" seems to mean here "most significant digit" (except for a(1)), while the "significance" is decreasing when going from the first to the last digit. (E.g., 1234 rounded to 2 significant digits is 1200, so "1,2" should be the first and second (and not fourth and third) significant digits.) [_M. F. Hasler_, Jun 03 2009]
%H Michael S. Branicky, <a href="/A069588/b069588.txt">Table of n, a(n) for n = 1..1000</a>
%p 11,seq(nextprime(10^j),j=1..30);
%o (Python)
%o from sympy import nextprime
%o def a(n): return 11 if n == 1 else nextprime(10**(n-1))
%o print([a(n) for n in range(1, 21)]) # _Michael S. Branicky_, Nov 11 2021
%K nonn,base
%O 1,1
%A _Amarnath Murthy_, Mar 25 2002
%E More terms from _Sascha Kurz_, Mar 28 2002
%E a(19) and beyond from _Michael S. Branicky_, Nov 11 2021
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