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Apocalypse primes: 10^665+a(n) has 666 decimal digits and is prime.
2

%I #23 Apr 08 2024 18:52:44

%S 123,1837,6409,7329,8569,8967,9663,13213,14943,16299,17053,17857,

%T 22611,24601,25261,25729,27847,30567,32413,33321,33379,34257,34557,

%U 34723,38097,39387,39787,39889,39973,43501,43719,44889,48139,49587,53683

%N Apocalypse primes: 10^665+a(n) has 666 decimal digits and is prime.

%C This sequence contains about 10^662 terms, the last of which is 10^666-1157.

%H Robert G. Wilson v, <a href="/A115983/b115983.txt">Table of n, a(n) for n = 1..6666</a>

%H Brady Haran and Tony Padilla, <a href="https://www.youtube.com/watch?v=KXO2l7Kh60A">Interesting 666-digit Numbers</a>, YouTube Numberphile video, 2024.

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

%t lst={};a=10^665;Do[If[PrimeQ[a+n], Print[n];AppendTo[lst, n]], {n, 8!}];lst (* _Vladimir Joseph Stephan Orlovsky_, Aug 30 2008 *)

%t Select[Range[55000],IntegerLength[10^665+#]==666&&PrimeQ[10^665+#]&] (* _Harvey P. Dale_, Jul 30 2019 *)

%K base,dumb,fini,nonn

%O 1,1

%A _Eric W. Weisstein_, Feb 09 2006