Big O notation

[math]\displaystyle{ \Theta(g(n)) = {f(n) : there exist positive constants c1,c2 and n0 such that 0<=''c''₁*g(n) <= f(n) <= c2*g(n) for all >= n0 } }[/math]

[math]\displaystyle{ O(g(n)) = {f(n) : there exist positive constants c1,c2 and n0 such that 0<=''c''₁*g(n) <= f(n) <= c2*g(n) for all >= n0 } }[/math]

[math]\displaystyle{ \Omega(g(n)) = {f(n) : there exist positive constants c1,c2 and n0 such that 0<=''c''₁*g(n) <= f(n) <= c2*g(n) for all >= n0 } }[/math]

[math]\displaystyle{ o(g(n)) = {f(n) : there exist positive constants c1,c2 and n0 such that 0<=''c''₁*g(n) <= f(n) <= c2*g(n) for all >= n0 } }[/math]