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 A064214 #6 May 01 2022 07:25:46
%S A064214 4,6,6,24,42,42,18,198,42,54,96,84,522,240,48,228,708,732,660,132,528,
%T A064214 390,78,1014,504,1008,1134,504,708,582,894,516,2982,810,162,1746,4758,
%U A064214 1848,414,4512,2928,1722,4392,1104,1134,1950,390,78,1500,300,60
%N A064214 Least k such that k*5^n +/- 1 are twin primes.
%t A064214 Do[ k = 1; While[ ! PrimeQ[ k*5^n + 1 ] || ! PrimeQ[ k*5^n - 1 ], k++ ]; Print[ k ], {n, 0, 50} ]
%Y A064214 Cf. A063983.
%K A064214 nonn
%O A064214 0,1
%A A064214 _Robert G. Wilson v_, Sep 21 2001
%E A064214 Offset corrected by _Georg Fischer_, May 01 2022