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 A066454 #8 Sep 18 2024 12:48:39 %S A066454 0,0,1,4,10,34,71,246,522,1783,3765,12858,27496,94525,203318,702789, %T A066454 1522315,5290592,11519095,40214441,87947507,308236670 %N A066454 Number of 3-dimensional polyominoes (or polycubes) with n cells and rotational symmetry group of order exactly 2. %C A066454 The sequence counts "one-sided" polycubes (A000162); chiral polycubes count twice. - _John Mason_, Sep 18 2024 %D A066454 W. F. Lunnon, Symmetry of cubical and general polyominoes, pp. 101-108 of R. C. Read, editor, Graph Theory and Computing. Academic Press, NY, 1972. %F A066454 a(n) = 2*B(n)+2*C(n)+J(n)+BE(n)+BF(n)+CE(n)+CK(n)+EE(n), see Lunnon paper for naming convention. - _John Mason_, Sep 18 2024 %Y A066454 Cf. A000162, A066453, A066273, A066281, A066283, A066287, A066288. %K A066454 nonn,more %O A066454 1,4 %A A066454 Brendan Owen (brendan_owen(AT)yahoo.com), Dec 27 2001 %E A066454 Name clarified and more terms from _John Mason_, Sep 18 2024