Reference · Non-negative rationals
rainbow.math.rational.nnrat.null-scaling
Scaling a null sequence by a bounded constant preserves convergence to zero: analysis/rate-null-scaled : c <= 1 -> rate-null s M -> rate-null (\n. c * s n) M Composes three earlier results: nnrat/multiply-right-monotone (c <= 1 => c*s n <= 1*s n), nnrat/multiply-one-left (1*s n ~ s n), transported by nnrat/at-most-respects-equivalence, then rate-null of s. Lets a geometric/harmonic error bound absorb a bounded prefactor. Native and axiom-free; chains nnrat-harmonic-convergence, nnrat-multiply-right-monotone, and nnrat-distributive on d63.
analysis/rate-null-scaled
analysis/rate-null-scaled : (c : ℚ≥0) (s : ℕ → ℚ≥0) (M : ℕ → ℕ) (hc : c ≤ 1) (hs : analysis/rate-null s M) → analysis/rate-null (fun n => c · s n) M
1 = nnrat/one· = nnrat/multiplyℕ = data/Natℚ≥0 = nnrat/NonnegativeRational≤ = nnrat/at-most