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 A243139 #18 Sep 08 2022 08:46:08 %S A243139 6,11,37,135,2059,8205,131089,524307,8388631,536870941,2147483679, %T A243139 137438953509,2199023255593,8796093022251,140737488355375, %U A243139 9007199254741045,576460752303423547,2305843009213694013,147573952589676412995,2361183241434822606919 %N A243139 a(n) = 2^prime(n) + prime(n). %H A243139 Vincenzo Librandi, <a href="/A243139/b243139.txt">Table of n, a(n) for n = 1..200</a> %H A243139 J. Mestel, <a href="/A005605/a005605.pdf">Archimedeans Problems Drive 1977</a>, Eureka, 39 (1978), 38-40. (Annotated scanned copy) %t A243139 f[n_]:=(2^Prime[n] + Prime[n]); Array[f, 80, 1] %o A243139 (Magma) [2^p + p: p in PrimesUpTo(80)]; %Y A243139 Cf. A034785, A100105. %K A243139 nonn %O A243139 1,1 %A A243139 _Vincenzo Librandi_, Jun 03 2014