Log2
The symbols log2, lb, or ld are used for the binary logarithm, also called dual logarithm or logarithm base two.
Log2 of the first primes
| Prime | Log2 prime |
|---|---|
| 2 | 1.000000000 |
| 3 | 1.584962501 |
| 5 | 2.321928095 |
| 7 | 2.807354922 |
| 11 | 3.459431619 |
| 13 | 3.700439718 |
| 17 | 4.087462841 |
| 19 | 4.247927513 |
| 23 | 4.523561956 |
| 29 | 4.857980995 |
You can calculate the binary logarithm of n using the identity:
$$ \log_2(n) = \ln(n) / \ln(2) $$