Sample representations:
Decimal(5): Hex(5), MySystem(5)
Decimal(15): Hex(F), MySystem(F)
Decimal(16): Hex(10), MySystem(G)
Decimal(17): Hex(11), MySystem(H)
Decimal(18): Hex(12), MySystem(I)
Decimal(19): Hex(13), MySystem(J)
Decimal(20): Hex(14), MySystem(10)
...