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 A291828 #7 Nov 07 2017 19:25:23
%S A291828 16,2048,34992,262144,1250000,4478976,13176688,33554432,76527504,
%T A291828 160000000,276922881,311794736,573308928,1003976272,1686616064,
%U A291828 2733750000,4294967296,6565418768,9795520512,14301947824,20480000000,28817416656,35446128768,39909726208
%N A291828 Numbers k such that k^2 is sum of two positive 7th powers.
%C A291828 When a^7 + b^7 = m, (ma)^7 + (mb)^7 = m^8 is square.
%C A291828 When k in this sequence, k*(n^7) (n = 2, 3, ... ) is also in this sequence.
%H A291828 Chai Wah Wu, <a href="/A291828/b291828.txt">Table of n, a(n) for n = 1..447</a>
%e A291828 16^2 = 2^8 = 2^7 + 2^7, so 16 is in the sequence.
%e A291828 276922881^2 = 129^7 + 358^7, so 276922881 is in the sequence.
%t A291828 lst={};Do[If[IntegerQ[(n^2-a^7)^(1/7)],AppendTo[lst,n]],{n,4*10^10},{a,(n^2/2)^(1/7)}]; lst
%Y A291828 Cf. A000290, A001015, A004431, A050801.
%K A291828 nonn
%O A291828 1,1
%A A291828 _XU Pingya_, Sep 03 2017