e
E
The e block is a reporter block that reports the value of Euler's constant (2.718281828459045..). To get the block, one must add the "Operators Expansion" extension.
However, when you do say (e::operators)or think (e::operators) it shortens into 2.72.
Workaround
This block can be worked around by using 1 as the input for the () of () operators block, the constant () block with e selected, or using anything else that reports the value of e. If this value is used multiple times in the code, a variable can be used.