Hello Werg,
I did not understand "then the rank is given to us by (3 - 1)*5! + (1-1)*4! + (3 -1)*3! + (3 - 1)*2! + (1-1)*1! + (1 - 1)*0! = 268"
"x in (x - 1)*n! is the rank of the number in respect to the numbers on its right in 315624"
what does this mean. Right...does it mean no. of digits...