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 A356201 #18 Sep 09 2022 14:50:44 %S A356201 0,4,106,2384,51196,958170,24341911,636875169,14536767750, %T A356201 285039411789,6322647312660,202105291334913 %N A356201 a(n) is the first component x of the distance vector (x,y), x >= y >= 0, between two nodes of an infinite square lattice of one-ohm resistors, such that the resistance R between the two nodes is as close as possible to n ohms, i.e., abs(R - n) is minimized. y is A356202(n). %C A356201 If more than one solution exists, the one maximizing x and minimizing y is chosen. %H A356201 Hugo Pfoertner, <a href="/A355565/a355565.gp.txt">PARI program for inverse problem</a>, (2022). Finds the grid point [x,y] that leads to the best approximation of a given resistance distance R (ohms) between [0,0] and [x,y]. %e A356201 n x y R(x,y) - n %e A356201 0 0 0 0 %e A356201 1 4 2 -8.076*10^(-3) %e A356201 2 106 8 7.349*10^(-6) %e A356201 3 2384 606 2.206*10^(-8) %e A356201 4 51196 24881 -7.426*10^(-11) %e A356201 5 958170 903855 7.396*10^(-16) %e A356201 6 24341911 18345919 -7.814*10^(-16) %e A356201 7 636875169 303176603 -3.017*10^(-19) %e A356201 8 14536767750 7423167971 5.874*10^(-21) %e A356201 9 285039411789 247828120179 -2.461*10^(-24) %e A356201 10 6322647312660 6034957650107 -1.048*10^(-26) %e A356201 11 202105291334913 7948827377158 1.795*10^(-29) %o A356201 (PARI) \\ using the function Rsqlatt(R) from the linked program %o A356201 for (k=0, 11, print1(Rsqlatt(k)[1], ", ")) \\ _Hugo Pfoertner_, Sep 09 2022 %Y A356201 Cf. A355565, A355566, A355567, A355953, A355955. %Y A356201 Cf. A356203, A356204 (similar for triangular lattice). %K A356201 nonn,hard,more %O A356201 0,2 %A A356201 _Hugo Pfoertner_, Aug 01 2022 %E A356201 a(9)-a(11) from _Hugo Pfoertner_, Aug 22 2022