```     |----+----+----+----+----+----2
|IGAM|BETA|IBET|ERF |BESJ|BESY|
|----+----+----+----+----+----|
|IMAG|CONJ| RE |ATN2|RAND|RAGN|
|----+----+----+----+----+----|
|GCD |FACT|DFCT|BNOM|PERM|NXTP|
|----+----+----+----+----+----|
```

This menu provides various operations from the f and k prefix keys.

<IMAG> multiplies the number on the stack by the imaginary number ‘i = (0, 1)’.

<RE> extracts the real part a complex number. INV RE extracts the imaginary part.

<RAND> takes a number from the top of the stack and computes a random number greater than or equal to zero but less than that number. (See Random Numbers.) <RAGN> is the “random again” command; it computes another random number using the same limit as last time.

<INV GCD> computes the LCM (least common multiple) function.

<INV FACT> is the gamma function. gamma(x) = (x-1)!’.

<PERM> is the number-of-permutations function, which is on the H k c key in normal Calc.

<NXTP> finds the next prime after a number. INV NXTP finds the previous prime.