Express 31 by 4 successive digits, using no more than 4 out of 5 basic operations (i.e. + - / * and exponentation), nothing else allowed.

No brackets!

The order of the digits must be an arithmetic progression like 8*7-6-5 or 3+4*5+6, examples fitting the specifications but not the result.

a. Straightforward answers:

6*5+4-3

4^3/2-1 ....might be others

b. Including concatenation (not precluded by the text!):

32-1-0

32-1+0

32-1^0

-1-2+34

2+34-5 .....might be others

c, Extra challenge: Disregard the order, as long as you use

only digits a, a+1, a+2, a+3:

65-34

34-2-1

32-5+4

54-23 ....plenty of others

The challenge is to expand lists a. b. and c. without introducing new operators - still no brackets.

Will publish the comprehensive expanded solution.

Good luck!

*Edited on ***August 14, 2018, 3:49 am**