50 Real analysis
51 Theory of functions of a real variable
52 Calculus
53 Infinite series and sequences. Summability. Improper integrals. Asymptotic behavior
54 Trigonometry. Orthogonal and Eigenvalue expansion. Fourier analysis
55 Harmonic analysis. Almost periodic functions. Banach algebras. C* algebras. Wavelets
56 Linear spaces. Functional analysis. Hilbert and Banach spaces
57 Integration and measure theory. Theory of distributions
58 Inequalities
59 Asymptotic expansions. Functional analysis