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 A036439 #20 Jul 02 2025 16:01:56
%S A036439 2,4,7,12,19,30,43,60,79,102,131,162,199,240,283,330,383,442,503,570,
%T A036439 641,714,793,876,965,1062,1163,1266,1373,1482,1595,1722,1853,1990,
%U A036439 2129,2278,2429,2586,2749,2916,3089,3268,3449,3640,3833,4030,4229,4440,4663
%N A036439 a(n) = a(n-1) + prime(n-1), with a(1)=2.
%C A036439 Old name was "a(n) = 2 + the sum of the first n-1 prime numbers".
%H A036439 Harvey P. Dale, <a href="/A036439/b036439.txt">Table of n, a(n) for n = 1..1000</a>
%t A036439 nxt[{n_,a_}]:={n+1,a+Prime[n]}; NestList[nxt,{1,2},50][[All,2]] (* _Harvey P. Dale_, Sep 21 2016 *)
%o A036439 (PARI) a(n) = 2 + sum(i=1, n-1, prime(i)); \\ _Michel Marcus_, Aug 12 2013
%Y A036439 A014284(n) + 1.
%K A036439 nonn,easy
%O A036439 1,1
%A A036439 Pavel Bubak (pbub6070(AT)beta.ms.mff.cuni.cz)
%E A036439 More terms from _James Sellers_, Feb 06 2000
%E A036439 Offset changed and definition improved from _Bruno Berselli_, Jul 30 2013