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 A095028 #6 Aug 18 2021 21:44:35
%S A095028 1,3,4,5,9
%N A095028 An example of a (v,k,lambda)=(11,5,2) cyclic difference set.
%C A095028 See A095029.
%H A095028 Dan Gordon, <a href="http://web.archive.org/web/20101226230341/http://www.ccrwest.org/diffsets/ds_list.pdf">List of Cyclic Difference Sets</a>, (2003).
%e A095028 Using the numbers {1 3 4 5 9}, every number in the range 1..10 can be written as a difference modulo 11 in two different ways:
%e A095028 1=4-3=5-4, 2=3-1=5-3, 3=4-1=(1-9) mod 11, 4=5-1=9-5, 5=9-4=(3-9) mod 11,
%e A095028 6=9-2=(4-9) mod 11, 7=(1-5) mod 11=(5-9) mod 11, 8=9-1=(1-4) mod 11,
%e A095028 9=(1-3) mod 11=(3-5) mod 11, 10=(3-4) mod 11=(4-5) mod 11.
%Y A095028 Cf. A095025 number of cyclic difference sets with n elements, A095029 .. A095047 more examples of cyclic difference set with k=5..53.
%K A095028 fini,full,nonn
%O A095028 1,2
%A A095028 _Hugo Pfoertner_, Jun 02 2004