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$$a^{\cdot\, n}=a\cdot a\cdots a$$ $$a^{\wedge\, n}=a\wedge a\wedge\dots\wedge a$$ $$a^{,\,n}=a,a,\dots,a$$ For example one could write $$\langle(x+10y-z)^{,\,2}\rangle= \langle(x+10y-z),(x+10y-z)\rangle.$$ or $$\sin^{\circ(-1)}x=\arcsin x$$ or $$\sin^{\cdot(-1)}x=\frac1{\sin x}$$