a) the set [N]^w of infinite subsets of N
N= natural number, w= sigma
b) the set [R]^c of subsets A within R where |A| = c
R = real number
c) the set C^(infinity) of smoot function f: R -> R.
C^(infinity) is C to the power of infinity
a) the set [N]^w of infinite subsets of N
N= natural number, w= sigma
b) the set [R]^c of subsets A within R where |A| = c
R = real number
c) the set C^(infinity) of smoot function f: R -> R.
C^(infinity) is C to the power of infinity