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 A294081 #17 Mar 24 2018 19:17:28
%S A294081 1,2,3,3,3,3,3,2,2,3,4,4,3,3,3,2,2,3,5,5,4,3,3,2,2,3,5,6,4,4,3,3,2,3,
%T A294081 5,5,5,4,5,3,3,4,5,5,3,4,4,3,2,3,6,7,6,5,6,5,4,3,4,5,3,4,4,4,3,4,7,7,
%U A294081 6,5,5,3,3,4,7,7,6,5,4,3,2,5,7,8,5,5,6
%N A294081 Number of partitions of n into three squares and two nonnegative 7th powers.
%C A294081 4^i(8j + 7) - 1^7 - 1^7 == 5 (mod 8) (when i = 0), or 2 (when i = 1), or 6 (when i >= 2). Thus, each nonnegative integer can be written as a sum of three squares and two nonnegative 7th powers; i.e., a(n) > 0.
%C A294081 More generally, each nonnegative integer can be written as a sum of three squares and a nonnegative k-th power and a nonnegative m-th power.
%H A294081 Wikipedia, <a href="https://en.wikipedia.org/wiki/Legendre%27s_three-square_theorem">Legendre's three-square theorem</a>
%H A294081 Wikipedia, <a href="https://en.wikipedia.org/wiki/Lagrange%27s_four-square_theorem">Lagrange's four-square theorem</a>
%e A294081 7 = 0^2 + 1^2 + 2^2 + 1^7 + 1^7 = 1^2 + 1^1 + 2^2 + 0^7 + 1^7, a(7) = 2.
%e A294081 10 = 0^2 + 0^2 + 3^2 + 0^7 + 1^7 = 0^2 + 1^1 + 3^2 + 0^7 + 0^7 = 0^2 + 2^2 + 2^2 + 1^7 + 1^7 = 1^2 + 2^1 + 2^2 + 0^7 + 1^7, a(10) = 4.
%t A294081 a[n_]:=Sum[If[x^2+y^2+z^2+u^7+v^7==n, 1, 0], {x,0,n^(1/2)}, {y,x,(n-x^2)^(1/2)}, {z,y,(n-x^2-y^2)^(1/2)}, {u,0,(n-x^2-y^2-z^2)^(1/7)}, {v,u,(n-x^2-y^2-z^2-u^7)^(1/7)}]
%t A294081 Table[a[n], {n,0,86}]
%Y A294081 Cf. A000164, A002635, A004215, A004771, A297970.
%K A294081 nonn
%O A294081 0,2
%A A294081 _XU Pingya_, Feb 09 2018