View Single Post
2021-09-19, 14:08   #5
Dr Sardonicus

Feb 2017
Nowhere

2×2,917 Posts

Quote:
 Originally Posted by LarsNet And to create a hilo map (this is an original discovery as far as i know while studying primes ) meaning map 1 to 5 through 9 and 0 to 0 through 4, use this equation: Code: a = 2**61-1 # 2305843009213693951 z = a + a z = int(str(z),16) h = (int(str(a), 16) + int(str(a), 16)) print(hex((z-h)//6) 2305843009213693951 0001100001000110110 The 0's align with 0-4 above the binary, and 1's align with 5-9 above the hex of (z-h)//6. The binary is in the hex, nice.
Congratulations. You've discovered that in the decimal addition a + a, there's a carry from places whose digits are greater than 4, and no carry from places whose digits are less than 5.