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 A227628 #22 Nov 17 2013 03:00:47
%S A227628 1,2,14,2,32,28,58,2,110,64,134,28,184,116,448,2,308,220,382,64,812,
%T A227628 268,554,28,752,368,974,116,872,896,994,2,1876,616,1856,220,1408,764,
%U A227628 2576,64,1724,1624,1894,268,3520,1108,2258,28,2746,1504
%N A227628 Number of Lipschitz quaternions X such that X^2 == X (mod n).
%H A227628 C. J. Miguel and R. Serodio, <a href="http://www.m-hikari.com/ija/ija-2011/ija-25-28-2011/miguelIJA25-28-2011-2.pdf">On the Structure of Quaternion Rings over Zp</a>, International Journal of Algebra, Vol. 5, 2011, no. 27, pp. 1313-1325.
%t A227628 cuaternios[n_] := Flatten[Table[{{ a, -b, d, -c}, {b, a, -c, -d}, {-d, c, a, -b}, {c, d, b, a}}, {a, n}, {b, n}, {c, n}, {d, n}], 3]; cuater[n_] := Length@Select[cuaternios[n], Mod[#.# - #, n] == 0*# &]; Table[cuater[n],{n,1,100}]
%Y A227628 Cf. A000118, A227477, A227499.
%K A227628 nonn,mult
%O A227628 1,2
%A A227628 _José María Grau Ribas_, Jul 18 2013