We're all familiar with factorial:
n>0,n!=n×(n−1)×⋯×(n−(n−1))
I've occasionally seen "plustorial":
n>0,n(plustorial)=n+(n−1)+…+(n−(n−1))
Some quick web searching indicates that there is some non-standard but somewhat common usage of the term "plustorial" to describe this, with shorthand being a double-dagger or an exclaimation point having a "+" rather than a dot beneath the vertical mark.
My question is: Is there a "real" standard name for this process and is there a standard corresponding shorthand? I understand that it could be written in sigma notation, was curious about something more terse.
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