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 A294428 #18 Aug 02 2025 18:12:14 %S A294428 2,4,6,8,7,10,12,14,16,18,17,20,21,23,24,28,26,30,32,33,34,38,36,40, %T A294428 42,43,44,46,47,50,49,52,54,55,57,59,61,62,65,64,67,68,69,71,75,73,77, %U A294428 79,81,80,83,85,87,88,91,90,93,95,94,97,99,101,103,104 %N A294428 Terms of A065188 that are below the main diagonal. %C A294428 This gives another way to view A199134. In fact, a(n) = A065188(A199134(n)). %H A294428 N. J. A. Sloane, <a href="/A294428/b294428.txt">Table of n, a(n) for n = 1..19000</a> %Y A294428 Cf. A065188, A199134, A275884, A294428. %K A294428 nonn %O A294428 1,1 %A A294428 _N. J. A. Sloane_, Nov 06 2017, based on an email from _Don Knuth_, Oct 31 2017