CHAR NUMBER ENTITY DESCRIPTION ∀ ∀ ∀ For all ∂ ∂ ∂ Partial diffrential ∃ ∃ ∃ The exists ∅ ∅ ∅ Empty sets ∇ ∇ ∇ Nabla ∈ ∈ ∈ Element of ∉ ∉ ∉ Not an element of ∋ ∋ ∋ Contains a member ∏ ∏ ∏ N-ary product ∑ ∑ ∑ N-ary summation