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 A046039 #26 Feb 16 2025 08:32:38
%S A046039 2,3,4,5,6,7,8,9,10,11,12,13,14,15,18,19,20,21,22,23,24,25,26,27,28,
%T A046039 29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,
%U A046039 52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74
%N A046039 Numbers which cannot be represented as a sum of distinct 4th powers.
%C A046039 Last term is a(889576) = 5134240. [_Charles R Greathouse IV_, Feb 26 2012]
%H A046039 Vaclav Kotesovec, <a href="/A046039/b046039.txt">Table of n, a(n) for n = 1..60000</a>
%H A046039 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/BiquadraticNumber.html">Biquadratic Number</a>
%t A046039 max = 2000; f[x_] := Product[1 + x^(k^4), {k, 1, 10}]; A003999 = Exponent[#, x]& /@ List @@ Normal[Series[f[x], {x, 0, max}]] // Rest; A046039 = Complement[Range[max], A003999][[1 ;; 71]](* _Jean-François Alcover_, Nov 09 2012, after _Charles R Greathouse IV_ *)
%o A046039 (PARI) select( is_A046039(n,m=n)={m^4>n&& m=sqrtnint(n,4); n!=m^4&& !while(m>1, is_A046039(n-m^4, m--)||return)}, [1..74]) \\ _M. F. Hasler_, Apr 21 2020
%Y A046039 Cf. A001422, A001476. Complement of A003999.
%Y A046039 Cf. A279487.
%K A046039 nonn,fini
%O A046039 1,1
%A A046039 _Eric W. Weisstein_