This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A110980 #31 Sep 08 2022 08:45:20 %S A110980 1,2,4,6,13,14,16,17,19,30,31,60,68,73,113,144,276,288,364,449,473, %T A110980 739,833,1171,1732,2292,3912,7673,9458,16982,19751,21479,23837,77726 %N A110980 Integers n such that 10^n+99 is prime. %C A110980 The next term, if one exists, is >100000. - _Robert Price_, Apr 25 2011 %C A110980 See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable or proved primes - search on "10w99". %H A110980 Makoto Kamada, <a href="https://stdkmd.net/nrr/prime/">List of near-repdigit-related prime numbers</a>. %H A110980 <a href="/index/Pri#Pri_rep">Index entries for primes involving repunits</a>. %e A110980 If n=6, we have 10^6+99 = 1000000+99 = 1000099, which is prime. %t A110980 Select[Range[78000],PrimeQ[10^#+99]&] (* _Harvey P. Dale_, Aug 23 2013 *) %o A110980 (Magma) [n: n in [1..400]| IsPrime(10^n+99)]; // _Vincenzo Librandi_, Nov 02 2014 %Y A110980 Cf. A049054, A088274, A088275, A095688, A107083, A108049, A108050, A108052, A108054. %K A110980 more,nonn %O A110980 1,2 %A A110980 Julien Peter Benney (jpbenney(AT)ftml.net), Sep 30 2005 %E A110980 a(1)=1 added by _Vladimir Joseph Stephan Orlovsky_, May 02 2008 %E A110980 a(29)-a(33) from _Robert Price_, Mar 22 2010 %E A110980 a(34)=77726 from _Robert Price_, Mar 03 2011