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 A275798 #12 Apr 27 2020 06:26:04
%S A275798 1,3,51,4274,2105872,4295278656,35184441295872,1152921514002096128,
%T A275798 151115727460762179076096,79228162514269052299408048128,
%U A275798 166153499473114502703835144588886016,1393796574908163946384646767619026404245504,46768052394588893382518536034792338549485151977472
%N A275798 One half of the number of n X n square grids with squares of two colors modulo operations of the dihedral group D_4.
%C A275798 See A054252(n, k) for the number of n X n square grids with squares from two colors modulo operations of the dihedral group D_4 with k colors of one sort.
%C A275798 One half of the row sums of A054252, starting with n=1. For the row sums starting with n=0 see A054247.
%H A275798 Andrew Howroyd, <a href="/A275798/b275798.txt">Table of n, a(n) for n = 1..50</a>
%F A275798 a(n) = (1/2)*Sum_{k=0..n^2} A054252(n, k).
%F A275798 a(n) = A054247(n)/2, n >= 1.
%Y A275798 Cf. A054252, A054247.
%K A275798 nonn,easy
%O A275798 1,2
%A A275798 _Wolfdieter Lang_, Oct 03 2016
%E A275798 Terms a(11) and beyond from _Andrew Howroyd_, Apr 26 2020