What is the formal definition of addition?
96091
How does ZFC describe addition?
70610
Why is ring addition commutative?
87855
Construction of the pre-addition
97667
If $a<b$, $c<d$ then $a+c<b+d$?
154319
Why do you add +1 in counting test questions?
56945
What does the math notation $\sum$ mean?
23270
The sum of powers of two and two's complement – is there a deeper meaning behind this?
108596
Proof by induction for "sum-of"
46212
What is the standard interpretation of order of operations for the basic arithmetic operations?
57172
Strange result with floating point addition
26317
How is moving the last digit of a number to the front and multiplying related to multiplicative orders?
128774
Unexpected result of summation
157280
How do I sum up specific things in Numbers?
91035
Why is x++-+-++x legal but x+++-+++x isn't?
88332
Why does 1.__add__(1) yield a syntax error?
101790
What's the function like sum() but for multiplication? product()?
60205
Sum in Mathematica gives extra "+List"