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 A030278 #11 Apr 22 2019 23:07:25
%S A030278 4,18,86,393,1790,7918,34047,142442,582768,2344913,9330350,36842164,
%T A030278 144611963,564509442,2191142528,8453688007,32411106626,123493645782,
%U A030278 467831766283,1763390759650,6619106543024,24762942068363,92393401202050,343951336690542
%N A030278 COMPOSE primes with primes.
%H A030278 N. J. A. Sloane, <a href="/transforms.txt">Transforms</a>
%F A030278 G.f.: Sum_{j>=1} prime(j)*(Sum_{k>=1} prime(k)*x^k)^j. - _Ilya Gutkovskiy_, Apr 21 2019
%Y A030278 Cf. A000040.
%K A030278 nonn
%O A030278 1,1
%A A030278 _Christian G. Bower_
%E A030278 Corrected and extended by _N. J. A. Sloane_, Oct 29 2006