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 A084955 #7 Feb 04 2020 06:35:14 %S A084955 2,3,7,13,13,13,541,4594309,64649503,7577449963,2005324830163, %T A084955 39676048812109,272235769110157,494535766350049 %N A084955 Initial prime of a prime chain of length n under the iteration x->2x+5. %C A084955 This is a special case of prime chains generated by f(x) = cx + d. %H A084955 D. H. Lehmer, <a href="https://doi.org/10.1112/plms/s3-14A.1.183">On certain chains of primes</a>, Proc. London Math. Soc. (3) 14a 1965 183-186. %e A084955 a(3)=7 since 7, 2*7+5=19 and 2*19+5=43 are primes. %Y A084955 Cf. A084954. %K A084955 nonn,more %O A084955 1,1 %A A084955 _W. Edwin Clark_, Jun 14 2003 %E A084955 More terms from _Don Reble_, Nov 07 2007