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 A353387 #10 Jul 13 2024 20:38:52
%S A353387 1,4,9,16,26,36,49,64,81,101,121,144,173,196,226,256,293,324,361,401,
%T A353387 441,484,529,576,626,677,729,784,842,904,961,1024,1089,1172,1226,1296,
%U A353387 1373,1444,1522,1601,1697,1764,1849,1936,2026,2116,2209,2304,2401,2504,2602,2708
%N A353387 a(n) is the least squared distance between 2 points of an n X n grid not occurring between two points of an (n-1) X (n-1) grid.
%o A353387 (PARI) a353387(nmax)={my(v=vectorsmall(2*nmax^2)); for(n=1,nmax,my(dfirst=0);
%o A353387 for(k=0,n,my(s=n^2+k^2); if(!v[s],if(!dfirst,print1(s,", ");dfirst=1); v[s]++)))};
%o A353387 a353387(52)
%Y A353387 Cf. A001105, A001481, A047800.
%Y A353387 First column of A353386.
%K A353387 nonn
%O A353387 2,2
%A A353387 _Hugo Pfoertner_, Apr 16 2022