su'i VUhU1 cmavo

n-ary mathematical operator: plus; addition operator; [(((a + b) + c) + ...)].


On affix form:

sumti
x1 is a/the argument of predicate/function x2 filling place x3 (kind/number).

In notes:

bai'ei
unary mathematical operator: successor/augment/increment (by one), succ(a) = a++ = a+1