That's ceil(log2(~4.8x10^44)) = 149 bits. But to make it efficiently decodable y...

		tromp 24 days ago \| parent \| context \| favorite \| on: No reachable chess position with more than 218 mov... That's ceil(log2(~4.8x10^44)) = 149 bits. But to make it efficiently decodable you'd use the ceil(log2(8726713169886222032347729969256422370854716254)) = 153 bit representation of the ChessPositionRanking project linked to in my other comment. The ChessCounter project does not provide an efficiently decodable code.