The digital root (also repeated digital sum) of a number is the (single digit) value obtained by an iterative process of summing digits, on each iteration using the result from the previous iteration to compute a digit sum. The process continues until a single-digit number is reached.
Simply, to find the digital root of a number, you take a number and add up all it's individual digits. If the sum is more than one digit, you add those digits together until you have a single-digit number.
For example, the digital root of 11 is 2 because 1+1= 2
The digital root of 123 is 6 because 1+2+3 = 6
Find the digital root of 234567; 2+3+4+5+6+7= 27
The digital root must be a single digit, therefore you must again add the digits of 27 together.
2+7 = 9
Making 9 the digital root of 234567
N 43 07.A B C
W 77 24.D E F
A= 44
B= 61
C= 110
D= 23513
E= 21341
F= 91837671
You can validate your puzzle solution with certitude.
Congratulations to BrotherTim for FTF !