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 A089049 #5 Oct 01 2018 10:14:30 %S A089049 0,0,0,0,1,1,1,2,2,1,2,2,2,2,3,1,2,1,2,2,3,2,3,1,2,2,3,1,3,1,1,0,2,1, %T A089049 2,2,3,2,3,1,3,2,3,1,3,1,1,0,2,2,3,1,3,1,1,0,3,1,1,0,1,0,0,0,2,1,2,2, %U A089049 3,2,3,1,3,2,3,1,3,1,1,0,3,2,3,1,3,1,1,0,3,1,1,0,1,0,0,0,2,2,3,1,3,1,1,0,3 %N A089049 Number of ways of writing n as a sum of exactly 4 powers of 2. %C A089049 The powers do not need to be distinct. %H A089049 Alois P. Heinz, <a href="/A089049/b089049.txt">Table of n, a(n) for n = 0..20000</a> %Y A089049 A column of A089052. Cf. A036987, A075897, A089048, A089050, A089051, A089053. %K A089049 nonn %O A089049 0,8 %A A089049 _N. J. A. Sloane_, Dec 03 2003