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 A061577 #9 Oct 19 2018 04:56:18
%S A061577 2,3,7,12,18,26,35,45,56,69,83,98,114,131,150,170,191,213,236,260,285,
%T A061577 312,340,369,399,430,462,495,529,565,602,640,679,719,760,802,845,889,
%U A061577 935,982,1030,1079,1129,1180,1232,1285,1339,1394,1451,1509,1568,1628
%N A061577 Sequence and first differences (A061578) include all numbers.
%C A061577 The lexicographically earliest sequence that begins with 2 and together with its first differences (A030124) contain every positive integer exactly once.
%C A061577 a(n) = A022953(n-1) for 2 < n <= 10000. - _Georg Fischer_, Oct 19 2018
%H A061577 Ivan Neretin, <a href="/A061577/b061577.txt">Table of n, a(n) for n = 1..10000</a>
%t A061577 Fold[Append[#1, #1[[#2]] + Complement[Range[Max@#1 + 1], #1][[#2]]] &, {2}, Range[50]] (* _Ivan Neretin_, Apr 04 2016 *)
%Y A061577 Cf. A005228, A022953, A061578.
%K A061577 nonn,easy
%O A061577 1,1
%A A061577 Ronald van Eijck (eequalsmcsquare(AT)hotmail.com), May 21 2001
%E A061577 More terms from Larry Reeves (larryr(AT)acm.org), Jun 12 2001