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 A363204 #14 Dec 09 2023 02:18:02 %S A363204 1,1,2,3,8,16,44,106,297,793,2259,6322,18212,52240,151818,440855, %T A363204 1288842,3767952,11058157,32452285,95467258 %N A363204 Number of free linear polycubes of size n, identifying rotations and reflections and avoiding the eight corner-connected neighbors. %C A363204 Linear polycubes have two end points with one neighbor, the remaining cubes all have two neighbors. %C A363204 When a cube [x,y,z] is in the polycube then neither of the eight cubes [x+-1,y+-1,z+-1] can be in the polycube. %e A363204 The polycubes for n <= 5 are: %e A363204 n=1: %e A363204 0,0,0 %e A363204 n=2: %e A363204 0,0,0; 0,0,1 %e A363204 n=3: %e A363204 0,0,0; 0,0,1; 0,0,2 %e A363204 0,0,0; 0,0,1; 0,1,0 %e A363204 n=4: %e A363204 0,0,0; 0,0,1; 0,0,2; 0,0,3 %e A363204 0,0,0; 0,0,1; 0,0,2; 0,1,0 %e A363204 0,0,0; 0,0,1; 0,1,1; 0,1,2 %e A363204 n=5: %e A363204 0,0,0; 0,0,1; 0,0,2; 0,0,3; 0,0,4 %e A363204 0,0,0; 0,0,1; 0,0,2; 0,0,3; 0,1,0 %e A363204 0,0,0; 0,0,1; 0,0,2; 0,1,0; 0,1,2 %e A363204 0,0,0; 0,0,1; 0,0,2; 0,1,0; 0,2,0 %e A363204 0,0,0; 0,0,1; 0,0,2; 0,1,0; 1,0,2 %e A363204 0,0,0; 0,0,1; 0,0,2; 0,1,2; 0,1,3 %e A363204 0,0,0; 0,0,1; 0,1,1; 0,1,2; 0,2,2 %e A363204 0,0,0; 0,0,1; 0,1,1; 0,2,1; 0,2,2 %Y A363204 Cf. A363203 (linear and avoiding at [0,0,+-2], [0,+-2,0], and [+-2,0,0]). %K A363204 nonn,more %O A363204 1,3 %A A363204 _Joerg Arndt_ and _Márk Péter Légrádi_, May 21 2023 %E A363204 a(19)-a(21) from _Joerg Arndt_, Dec 09 2023