\(t\)	time
\(r\)	Discount rate
\(V(r)\)	Present value
\(C(t)\)	A cash flow
\(\delta(t)\)	A point mass at time 0
\(a\)	A rate of growth or decay
\(\mathcal{L\lbrack}f\rbrack\)	The LaPlace transform expressed as operator on a distribution \(f\)
\(F(s)\)	The LaPlace transform of distribution \(f(t)\) as a distribution in \(s\)
\(f*g\)	The convolution of distributions \(f\) and \(g\)
\(|A|\)	The amplitude of a wave
\(\omega\)	Wave frequency
\(\theta\)	The phase of a wave
\(s\)	A complex number
\(i\)	\(\sqrt{- 1}\)
\(\alpha\)	The real part of a complex number
\(\overline{s}\)	The complex conjugate of \(s\)
\(x\)	A real number
\(\widetilde{f}\)	The Fourier transform of \(f\)
\(\varphi_{X}\)	The characteristic function of random variable X
\(N\)	The number of observations in a time series
\(x(n)\)	An observation of a time series
\(X(k)\)	A coefficient of the interpolating series of complex exponentials for \(\omega = 2\pi k/N\)