:: deftheorem Def2 defines Anti-subsymmetric MATRIX17:def 2 :
for K being Field
for n being Nat
for M being Matrix of n,K holds
( M is Anti-subsymmetric iff for i, j, k, l being Nat st [i,j] in Indices M & k = (n + 1) - j & l = (n + 1) - i holds
M * (i,j) = - (M * (k,l)) );