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 A178436 #14 Jan 17 2019 13:44:08
%S A178436 2,4,5,14,44,64,103,282,643,670,818,1092,1775,1856,4080,4178,4498,
%T A178436 6815,8293,10112,12023,13643
%N A178436 Numbers n such that 10^n - 77 is prime.
%C A178436 The next term, if one exists, is >100000. - _Robert Price_, Apr 25 2011
%C A178436 See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable or proved primes - search on "99923".
%H A178436 Makoto Kamada, <a href="https://stdkmd.net/nrr/prime/">List of near-repdigit-related prime numbers</a>.
%H A178436 <a href="/index/Pri#Pri_rep">Index entries for primes involving repunits</a>.
%e A178436 10^4 - 77 = 9923 which is a prime number.
%t A178436 nMax=1000; Do[If[PrimeQ[10^n-77], Print[n]], {n, nMax}]
%o A178436 (PARI) is(n)=ispseudoprime(10^n-77) \\ _Charles R Greathouse IV_, Jun 13 2017
%Y A178436 Cf. A108330, A108328.
%K A178436 more,nonn
%O A178436 1,1
%A A178436 _Robert Price_, Dec 21 2010