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 A125516 #9 Aug 12 2025 19:22:11
%S A125516 29,41,53,59,61,83,89,101,107,109,113,131,137,139,149,157,173,179,181,
%T A125516 197,211,227,229,233,241,251,257,269,277,281,283,293,307,313,317,331,
%U A125516 337,347,349,353,373,379,389,397,401,409,419,421,433,443,449,457,461
%N A125516 Prime numbers that are the sum of three distinct positive squares.
%H A125516 Zak Seidov, <a href="/A125516/b125516.txt">Table of n, a(n) for n = 1..1000</a>
%e A125516 29 = 2^2 + 3^2 + 4^2 = 4 + 9 + 16.
%e A125516 89 = 2^2 + 6^2 + 7^2 = 4 + 36 + 49; also 89 = 3^2 + 4^2 + 8^2 = 9 + 16 + 64.
%e A125516 353 = 2^2 + 5^2 + 18^2 = 4 + 25 + 324; also 353 = 4^2 + 9^2 + 16^2 = 16 + 81 + 256.
%t A125516 Select[Total/@Subsets[Range[20]^2,{3}],PrimeQ]//Union (* _Harvey P. Dale_, Aug 12 2025 *)
%o A125516 (PARI) {m=22;p=m^2;v=vector(m,x,x^2);w=[];for(i=1,m-2,for(j=i+1,m-1,for(k=j+1,m,if((n=v[i]+v[j]+v[k])<p&&isprime(n),w=concat(w,n)))));w=listsort(List(w),1);for(j=1,#w-1,print1(w[j],","))} /* Klaus Brockhaus, Feb 11 2007 */
%Y A125516 Cf. A088348, A126657, A126658.
%K A125516 nonn
%O A125516 1,1
%A A125516 _Tomas Xordan_, Jan 21 2007
%E A125516 Edited, corrected and extended by _Klaus Brockhaus_, Feb 11 2007