A trick I learned -- I think from Colin Wright -- involves powers of 2.
* Write the powers of 2 up to 2^10 in lex order and pop a decimal point after the first digit of each:
* 1.28
* 1.6
* 2
* 2.56
* 3.2
* 4
* 5.12
* 6.4
* 8
The logs of these are approximately 0.1, 0.2, 0.3, etc.
This is to do with 2^10 being about 10^3; you can do something very similar with powers of 5, but I find those harder to remember.
* Write the powers of 2 up to 2^10 in lex order and pop a decimal point after the first digit of each: * 1.28 * 1.6 * 2 * 2.56 * 3.2 * 4 * 5.12 * 6.4 * 8
The logs of these are approximately 0.1, 0.2, 0.3, etc.
This is to do with 2^10 being about 10^3; you can do something very similar with powers of 5, but I find those harder to remember.