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\[ \begin {array}{rclcl} u_{t} &=& u_{xx}+u(1-u),&\qquad& t>0,\ 0<x<l \\[0.5em] u(0,x) &=& \delta(x-1),&& 0<x<l \\ u(t,0)\ =\ 0 &=& u(t,l), && t>0 \\[1.2em] &&&& \end {array} \]

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