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Log 10-primes: primes in the initial decimal digits of log(10).
2

%I #24 Sep 13 2021 11:51:00

%S 2,23,2302585092994045684017991454684364207601

%N Log 10-primes: primes in the initial decimal digits of log(10).

%C The next term (a(4)) has 242 digits. - _Harvey P. Dale_, Sep 13 2021

%H Eric W. Weisstein, <a href="/A228241/b228241.txt">Table of n, a(n) for n = 1..5</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/ConstantPrimes.html">Constant Primes</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/IntegerSequencePrimes.html">Integer Sequence Primes</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/NaturalLogarithmof10Digits.html">Natural Logarithm of 10 Digits</a>

%t Module[{nn=500,l10},l10=RealDigits[Log[10],10,nn][[1]];Select[ Table[ FromDigits[ Take[l10,n]],{n,nn}],PrimeQ]] (* _Harvey P. Dale_, Sep 13 2021 *)

%Y Cf. A228240 (integer lengths of log(10)-primes).

%Y Cf. A002392 (decimal expansion of log(10)).

%K nonn,base

%O 1,1

%A _Eric W. Weisstein_, Aug 17 2013