https://jasper-aa64.github.io/tags/math/Recent content in Math on JasperHugoen-usTue, 28 Apr 2026 00:00:00 +0800https://jasper-aa64.github.io/posts/matrix-1-fast-exponentiation/Tue, 28 Apr 2026 00:00:00 +0800https://jasper-aa64.github.io/posts/matrix-1-fast-exponentiation/Matrix fast power for linear recurrences (4 patterns), 4 semiring templates (count/bool/min-plus/max-plus), matrix+segment tree for range-add Fibonacci queries, Kitamasa O(k²logn) and NTT O(k log²k logn).https://jasper-aa64.github.io/posts/matrix-2-gaussian-elimination/Tue, 28 Apr 2026 00:00:00 +0800https://jasper-aa64.github.io/posts/matrix-2-gaussian-elimination/Gauss elimination: real/mod/mod-2 templates (solve, det, inv, rank); incremental online RREF; Extended Lights Out, CF 1344F abstract GF(2) modelling, 2024 ICPC Kunming interactive tree queries.https://jasper-aa64.github.io/posts/matrix-3-linear-basis/Tue, 28 Apr 2026 00:00:00 +0800https://jasper-aa64.github.io/posts/matrix-3-linear-basis/XOR linear basis: full template with kth, range basis, normalisation; Nowcoder median example; CF 1101G prefix-XOR rank; gym 104768 C XOR-divisibility; Simplex LP solver.https://jasper-aa64.github.io/posts/matrix-4-problems/Tue, 28 Apr 2026 00:00:00 +0800https://jasper-aa64.github.io/posts/matrix-4-problems/Hard matrix problems: Fibonacci squared subarray sum with segment-tree 4-tuple and companion matrix; cycle-decomposition partition state space for random-swap sorting, first-step analysis, and Gaussian elimination.https://jasper-aa64.github.io/posts/number-theory-0-common-formulae/Tue, 28 Apr 2026 00:00:00 +0800https://jasper-aa64.github.io/posts/number-theory-0-common-formulae/Legendre’s formula, divisor and multiple convolutions in O(n log n), offline-difference batch processing for H(n)=Σf(d)g(⌊n/d⌋).https://jasper-aa64.github.io/posts/number-theory-1-elementary/Tue, 28 Apr 2026 00:00:00 +0800https://jasper-aa64.github.io/posts/number-theory-1-elementary/GCD/LCM properties, Bézout/Frobenius, Euler’s theorem with power-tower reduction and φ-chain technique, congruence system merging via exGCD, CRT, and n! prime factorisation via Legendre’s formula.https://jasper-aa64.github.io/posts/number-theory-1-1-divisibility-blocking/Tue, 28 Apr 2026 00:00:00 +0800https://jasper-aa64.github.io/posts/number-theory-1-1-divisibility-blocking/Divisibility blocking for O(sqrt n) floor-sum evaluation: lemma, single-variable loop, O(1) interval sum requirements, two-variable min-trick, multi-variable pseudocode, and ceiling-division blocking.https://jasper-aa64.github.io/posts/number-theory-2-ex-mobius-practice/Tue, 28 Apr 2026 00:00:00 +0800https://jasper-aa64.github.io/posts/number-theory-2-ex-mobius-practice/Practice problems for Möbius inversion: LCMSUM, two-variable lcm sum (O(n^3/4)), FSF’s game with offline difference, divisor-count sum d(ij), Omega Numbers with Dirichlet suffix sum.https://jasper-aa64.github.io/posts/number-theory-2-ex-mobius-techniques/Tue, 28 Apr 2026 00:00:00 +0800https://jasper-aa64.github.io/posts/number-theory-2-ex-mobius-techniques/Seven core techniques for Möbius inversion problems: loop shortening, gcd indicator expansion, coprimality reduction, Dirichlet convolution via T=dk, divisor symmetry, diagonal symmetry, and value-domain cnt[] tricks.https://jasper-aa64.github.io/posts/number-theory-2-multiplicative-functions/Tue, 28 Apr 2026 00:00:00 +0800https://jasper-aa64.github.io/posts/number-theory-2-multiplicative-functions/Multiplicative functions, single-point and linear-sieve evaluation; Möbius function, both forms of Möbius inversion with full derivations and examples; Dirichlet convolution, key identities, Du Jiao sieve; generalized Möbius inversion on posets.https://jasper-aa64.github.io/posts/number-theory-3-sieve-mobius-inclusion-exclusion/Tue, 28 Apr 2026 00:00:00 +0800https://jasper-aa64.github.io/posts/number-theory-3-sieve-mobius-inclusion-exclusion/Eratosthenes sieve for μ; g/f/h framework; Conclusions 1 and 2 with derivations and tables; GCD table intuition; CF 803F Coprime Subsequences with bottom-up and Möbius approaches.https://jasper-aa64.github.io/posts/number-theory-3-1-sieve-problems/Tue, 28 Apr 2026 00:00:00 +0800https://jasper-aa64.github.io/posts/number-theory-3-1-sieve-problems/Greedy optimality for divisibility-chain coin systems, DP over the maximum denomination, and a sieve-style transition by adding one larger coin.https://jasper-aa64.github.io/posts/number-theory-4-min25-du-jiao-sieve/Tue, 28 Apr 2026 00:00:00 +0800https://jasper-aa64.github.io/posts/number-theory-4-min25-du-jiao-sieve/Min_25 sieve: theory, two complete examples, Lagrange interpolation for power sums. Du Jiao sieve: template, P3768, GCD sum, LCM sum.https://jasper-aa64.github.io/posts/number-theory-4-primality-factorisation-residues/Tue, 28 Apr 2026 00:00:00 +0800https://jasper-aa64.github.io/posts/number-theory-4-primality-factorisation-residues/Miller-Rabin primality test, Pollard Rho factorisation, Tonelli-Shanks for quadratic residues, cubic residues via F_p[t]/(t^3-a), quartic residues by double square root, and general k-th residues via primitive root + BSGS, plus N-th residues mod composite.https://jasper-aa64.github.io/posts/combinatorics-order-theory/Sun, 26 Apr 2026 00:00:00 +0000https://jasper-aa64.github.io/posts/combinatorics-order-theory/Chromatic polynomial, chordal/interval graphs, PEO product formula, order polynomials (chain/antichain/tree/DAG/divisor lattice), MacMahon formula, Dilworth, Mirsky, Hall’s marriage theorem, Erdős–Szekeres, missile interception.https://jasper-aa64.github.io/posts/combinatorics-2-ex1-difference-convolution/Sat, 25 Apr 2026 00:00:00 +0000https://jasper-aa64.github.io/posts/combinatorics-2-ex1-difference-convolution/Cross-correlation via ordinary convolution: reverse-A and reverse-B extraction methods, derivation, and Ring Trick II (cyclic shift score maximisation via difference convolution).https://jasper-aa64.github.io/posts/combinatorics-2-ex2-cyclic-convolution/Sat, 25 Apr 2026 00:00:00 +0000https://jasper-aa64.github.io/posts/combinatorics-2-ex2-cyclic-convolution/Cyclic convolution definition, FFT/NTT implementation for n=2^k, zero-padding, why n must be a power of two, and the fold-back technique for arbitrary n.https://jasper-aa64.github.io/posts/combinatorics-2-1-fft-lagrange-interpolation/Sat, 25 Apr 2026 00:00:00 +0000https://jasper-aa64.github.io/posts/combinatorics-2-1-fft-lagrange-interpolation/Polynomial representations, FFT/DFT over complex numbers, Triple Sums, Fuzzy Search (difference convolution), FFT template, Lagrange interpolation (O(n²) and O(n) equidistant), sum of k-th powers, Assigning Prizes polynomial DP.https://jasper-aa64.github.io/posts/combinatorics-2-2-primitive-roots-ntt/Sat, 25 Apr 2026 00:00:00 +0000https://jasper-aa64.github.io/posts/combinatorics-2-2-primitive-roots-ntt/Order and primitive roots (Euler’s theorem, BSGS, exBSGS), discrete index as logarithm analogue, SGU 261 Discrete Roots, NTT theory and templates, divide-and-conquer NTT (product tree), Wannafly D team selection, Nowcoder 50F generating functions.https://jasper-aa64.github.io/posts/combinatorics-3-1-ordinary-generating-functions/Sat, 25 Apr 2026 00:00:00 +0000https://jasper-aa64.github.io/posts/combinatorics-3-1-ordinary-generating-functions/Formal power series basics, ordinary generating functions, inversion identities, generalized binomial expansions, bounded counting examples, and recurrence-to-closed-form examples such as Fibonacci and Catalan.https://jasper-aa64.github.io/posts/combinatorics-3-2-more-operations-on-formal-power-series/Sat, 25 Apr 2026 00:00:00 +0000https://jasper-aa64.github.io/posts/combinatorics-3-2-more-operations-on-formal-power-series/Newton iteration for polynomial inverse and square root, derivative/integral/composition of formal power series, logarithm and exponential of series, and worked examples including CF438E and a bad-modulus complete-knapsack generating function.https://jasper-aa64.github.io/posts/combinatorics-1-1-permutations-combinations/Fri, 24 Apr 2026 00:00:00 +0000https://jasper-aa64.github.io/posts/combinatorics-1-1-permutations-combinations/Hockey Stick identity, addition/multiplication principles, binomial identities, example problems: bitonic sequences, multiset permutations, multi-layer coloring DP, CCPC Subpermutation.https://jasper-aa64.github.io/posts/combinatorics-d1-diophantine-equations/Fri, 24 Apr 2026 00:00:00 +0000https://jasper-aa64.github.io/posts/combinatorics-d1-diophantine-equations/Stars and bars, bounded Diophantine equations via inclusion-exclusion, prefix-sum DP, D&C NTT, equal-cap formula, and a full worked example on CF 2127F.https://jasper-aa64.github.io/posts/combinatorics-0-common-formulae-conclusions/Mon, 20 Apr 2026 00:00:00 +0000https://jasper-aa64.github.io/posts/combinatorics-0-common-formulae-conclusions/A compact toolkit of geometric sums, floor-sum transformations, XOR facts, Fibonacci identities, and perfect-square patterns.https://jasper-aa64.github.io/posts/combinatorics-1-counting-conclusions/Mon, 20 Apr 2026 00:00:00 +0000https://jasper-aa64.github.io/posts/combinatorics-1-counting-conclusions/常见计数结论、Lucas 定理、不定方程解计数、平面分拆、DAG 路径计数、多项式平移、XOR 均匀性与若干竞赛常用结论。https://jasper-aa64.github.io/posts/combinatorics-1-2-inclusion-exclusion-diophantine-derangements/Mon, 20 Apr 2026 00:00:00 +0000https://jasper-aa64.github.io/posts/combinatorics-1-2-inclusion-exclusion-diophantine-derangements/Inclusion-exclusion in set and operator form, equal-count subproblems, bounded Diophantine counting, derangements, Stirling numbers, and selected contest problems.