Number Theory #0 April 28, 2026 2 min readCommon Formulae — Legendre's Formula & Divisor ConvolutionsLegendre’s formula, divisor and multiple convolutions in O(n log n), offline-difference batch processing for H(n)=Σf(d)g(⌊n/d⌋).#math#number-theory#convolution#divisor#legendre
