%I #6 Jan 27 2021 05:34:58
%S 1,64,1126,1653,13680,27453
%N Numbers k such that the first k digits of log_10(2) after the decimal point are primes.
%e 1 is listed because 3 is prime but 5 is not listed because 30102 is not prime.
%t Do[ If[ PrimeQ[ FromDigits[ RealDigits[ N[ Log[10, 2], n + 10], 10, n] [ [1] ] ] ], Print[n] ], {n, 1, 10000} ]
%Y Cf. A007524.
%K nonn,base,more
%O 1,2
%A John Sillcox (JMS21187(AT)aol.com), Apr 15 2003
%E Offset corrected and a(5)-a(6) added by _Amiram Eldar_, Jan 27 2021
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