Which 4-digit number has all these properties?
- its second digit is twice the first,
- its fourth digit is three times the third,
- all its digits are different,
- no two of its digits are consecutive.
The 7puzzle Challenge
The playing board of the 7puzzle game is a 7-by-7 grid containing 49 different numbers, ranging from 2 up to 84.
The 1st & 6th columns of the playing board contain the following fourteen numbers:
7 13 21 22 27 30 36 40 49 54 55 56 60 64
Which two numbers, when each is doubled, also appear on the list?
. . . can be found when clicking this.