Pseudo-differential operators of multiple symbol and the Calder\'on-Vaillancourt theorem
Pseudo-differential operators of multiple symbol and the Calder\'on-Vaillancourt theorem
In the present paper we shall define a class $S_{\lambda.\rho.\delta^{\tilde{m}_{\nu}}}^{\tilde{m}_{\nu\sim}}$' of multiple symbol as an extension of the class $S_{\rho.\dot{\delta}^{m^{\prime}}}^{m}$ of double symbol in our previous paper [6], where $\tilde{m}.=$ $(m_{1}, \cdots , m_{\nu})$ and $\tilde{m}_{\nu}^{\prime}=(m_{0}^{\prime}, m_{1}^{\prime}, \cdots , m_{\nu}^{f})$ are real vectors and $m_{j}^{\prime}\geqq 0,$ $j=0,1,$ $\cdots$ , $\nu$ …