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 A193993 #7 Mar 30 2012 17:23:02
%S A193993 1,3,9,5,72,27,49,8,12,216,11,24,7,147,36,10,336,36,361,188,231,8,529,
%T A193993 39,80,21,21,126,11,108,1986,14,51,1008,636,31,34,1083,36,152,11,693,
%U A193993 3786,8,24,1587,2209,51,56,56,1440,19,5832,63,33,203,1653,9,3481
%N A193993 Number of zeros in the period of Fibonacci 4-step sequence A000078 mod n.
%H A193993 Vincenzo Librandi, <a href="/A193993/b193993.txt">Table of n, a(n) for n = 1..200</a>
%t A193993 n = 4; Table[a = Join[{1}, Table[0, {n - 1}]]; a = Mod[a, i]; a0 = a; k = 0; zeros = 0; While[k++; s = Mod[Plus @@ a, i]; a = RotateLeft[a]; If[s == 0, zeros++]; a[[n]] = s; a != a0]; zeros, {i, 100}]
%Y A193993 Cf. A106295 (period of Lucas 4-step sequence).
%K A193993 nonn
%O A193993 1,2
%A A193993 _T. D. Noe_, Aug 18 2011