Generalized Skew Hadamard Difference Sets
  A skew Hadamard difference set (SHDS) is a difference set that satisfies the skew condition. It is known that if a group G admits a skew hadamard difference set, then G is a p-group with order congruent to 3 modulo 4. We will generalize skew Hadamard difference sets to Generalized Skew Hadamard Difference Sets (GSHDS) to cover the case when p is congruent to 1 module 4, and we will extend all known results that yield necessary existence conditions of skew Hadamard difference sets to our generalization, including the known exponent bounds. We will also show a set of necessary existence conditions a special family of groups. We will close the article with a general p-divisibility condition of the difference intersection numbers of a GSHDS for a special class of subgroups L. 
Carlos Salazar-Lazaro
math.CO