/ and \dfn1 / or \Create a monadic function which is equivalent to inserting dfn between each pair of elements in its argument. The function produced by \ records each step in its result, / returns only the final answer.
For example:
1+2+3+4+5 Result: 15 +/(1 2 3 4 5) Result: 15 +\(1 2 3 4 5) Result: (1 3 6 10 15)
The ContextException is thrown if dfn is not dyadic.