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 A267826 #20 Apr 08 2016 03:34:49
%S A267826 18,22,39,60,63,74,76,77,100,103,106,107,117,126,178,180,201,215,228,
%T A267826 230,245,271,289,291,295,315,341,356,357,393,413,419,420,480,481,523,
%U A267826 559,606,616,671,673,705,854,855,963,980,981,998,1103,1121,1130,1298,1484,1510,1643,1729,1849,1916,1934,1946
%N A267826 Numbers not of the form w^3 + 2*x^3 + 3*y^3 + 4*z^3, where w, x, y and z are nonnegative integers.
%C A267826 Conjecture: The sequence has exactly 122 terms the last of which is a(122) = 41405.
%C A267826 We have verified that there are no terms between 41406 and 2*10^5.
%C A267826 The conjecture implies that {P(v)+w^3+2*x^3+3*y^3+4*z^3: w,x,y,z = 0,1,2,...} = {0,1,2,...} whenever P(v) is among the polynomials a*v^3 (a = 1,5,6,7,9,10,12,15,18), b*v^4 (b = 1,2,3,5,6,12,18), c*v^5 (c = 1,2,5,12) and d*v^k (d = 5,12; k = 6,7). Moreover, it also implies that {8*t+w^3+2*x^3+3*y^3+4*z^3: t = 0,1; w,x,y,z = 0,1,2,...} = {0,1,2,...}. If a,b,c,d and m are positive integers with {m*t+a*w^3+b*x^3+c*y^3+d*z^3: t = 0,1; w,x,y,z = 0,1,2,...} = {0,1,2,...}, then we must have m = 8 and {a,b,c,d} = {1,2,3,4}.
%H A267826 Zhi-Wei Sun, <a href="/A267826/b267826.txt">Table of n, a(n) for n = 1..122</a>
%H A267826 Zhi-Wei Sun, <a href="http://listserv.nodak.edu/cgi-bin/wa.exe?A2=NMBRTHRY;7616eef.1604">Universal sums u^3+a*v^3+b*x^3+c*y^3+d*z^3 with u, v, x, y, z nonnegative integers</a>, a message to Number Theory Mailing List, April 3, 2016.
%e A267826 a(1) = 18 since it is the first nonnegative integer not in the set {w^3 + 2*x^3 + 3*y^3 + 4*z^3: w,x,y,z = 0,1,2,...}.
%t A267826 CQ[n_]:=CQ[n]=IntegerQ[n^(1/3)]
%t A267826 n=0;Do[Do[If[CQ[m-4*z^3-3y^3-2x^3],Goto[aa]],{z,0,(m/4)^(1/3)},{y,0,((m-4z^3)/3)^(1/3)},{x,0,((m-4z^3-3y^3)/2)^(1/3)}];n=n+1;Print[n," ",m];Label[aa];Continue,{m,0,1946}]
%Y A267826 Cf. A000578, A002804, A022566, A267861, A271099, A271169, A271237.
%K A267826 nonn
%O A267826 1,1
%A A267826 _Zhi-Wei Sun_, Apr 07 2016