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Smallest prime beginning with exactly n 1's.
17

%I #26 Sep 06 2023 06:57:16

%S 2,13,11,1117,11113,111119,11111101,11111117,111111113,11111111129,

%T 11111111113,1111111111139,11111111111123,1111111111111013,

%U 1111111111111123,11111111111111101,11111111111111119

%N Smallest prime beginning with exactly n 1's.

%C Largest terms are only probable primes. Some terms of the sequence are also in A004022 (repunit primes) or A056710 (all digits same except last digit). All terms of A004022 are in the current sequence.

%C According to the Magma Calculator (at http://magma.maths.usyd.edu.au/calc/), all 201 terms in the table (and thus all 17 terms listed above) are, in fact, prime. - _Jon E. Schoenfield_, Aug 24 2009

%H M. F. Hasler, <a href="/A065584/b065584.txt">Table of n, a(n) for n = 0..200</a>

%Y Cf. A065821, A068103, A068104, A068105.

%Y Cf. A004022 (repunit primes), A056710 (near-repdigit primes).

%K nonn,base

%O 0,1

%A _Robert G. Wilson v_, Nov 28 2001

%E Corrected by _Don Reble_, Jan 17 2007

%E Offset corrected by _Sean A. Irvine_, Sep 06 2023