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 A064218 #5 May 01 2022 13:19:45
%S A064218 4,3,6,3,18,240,24,3,174,93,57,141,465,501,105,822,552,324,555,237,
%T A064218 867,1488,543,2556,1050,105,51,429,1470,147,567,1329,636,5016,645,
%U A064218 4713,1116,1029,462,567,5757,951,5547,1245,2823,5931,1989,525,6246,1716
%N A064218 Least k such that k*10^n +/- 1 are twin primes.
%t A064218 Do[ k = 1; While[ ! PrimeQ[ k*10^n + 1 ] || ! PrimeQ[ k*10^n - 1 ], k++ ]; Print[ k ], {n, 0, 50} ]
%Y A064218 Cf. A063983, A064213, A064214, A064215, A064217, A064220, A064221.
%K A064218 nonn
%O A064218 0,1
%A A064218 _Robert G. Wilson v_, Sep 21 2001
%E A064218 Offset corrected by _Georg Fischer_, May 01 2022