No, Maganese is a fictious element. In fact this is the first time I've heard of it.
Mn
Mn
Manganese, element #25 on the periodic table.
Manganese is a meta element. Atomic number of it is 25.
Manganese is a metal element. Atomic mass of it is 55.
Manganese is an element made up of 25 protons and 25 electrons.
Manganese is a key alloying element in many types of steel and stainless steels.
There is no element with symbol a or A even
The symbol for the element Terbium is Tb
The element symbol for nitrogen is (N).
As is the symbol for the element arsenic.