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 A024581 #17 Jan 27 2019 08:49:08
%S A024581 1,3,8,22,60,163,443,1204,3273,8897,24185,65742,178705,485771,1320462,
%T A024581 3589388,9756968,26522189,72094784,195973941,532712403,1448062445,
%U A024581 3936241831,10699814642,29085111709,79061530637,214911522061,584190085145
%N A024581 a(n) = integer nearest e*a(n-1), where a(0) = 1.
%H A024581 Clark Kimberling, <a href="/A024581/b024581.txt">Table of n, a(n) for n = 0..250</a>
%H A024581 Steve Butler, R. L. Graham & Nan Zang, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL11/Butler/butler8.html">Jumping Sequences</a>, Journal of Integer Sequences, Vol. 11, 2008, 08.4.5.
%t A024581 a[0] = 1; a[n_] := Round[E*a[n - 1]];
%t A024581 Table[a[n], {n, 0, 30}]
%t A024581 (* _Clark Kimberling_, Aug 18 2012 *)
%t A024581 NestList[Floor[E*#+1/2]&,1,30] (* _Harvey P. Dale_, Jan 10 2013 *)
%o A024581 (PARI) lista(nn) = {nn++; my(va = vector(nn)); va[1] = 1; for (n=2, nn, va[n] = round(exp(1)*va[n-1]);); va;} \\ _Michel Marcus_, Jan 27 2019
%Y A024581 Equals row sums of triangle A153583. [_Gary W. Adamson_, Dec 28 2008]
%K A024581 nonn
%O A024581 0,2
%A A024581 _Clark Kimberling_