cara membuat algoritma ganjil genap

Genap =  2n  ; 2(1) = 2, 2(2) = 4, 2(8) = 16 ,dst.
Ganjil = 2n + 1; 2(1) + 1 = 3; 2(2)+1 = 5, 2(8)+1 = 17, dst