combinatorics-calculator
Calculate combinatorial values with modular arithmetic
npx skills add a5c-ai/babysitter --skill combinatorics-calculator --agent claude-code
Same command for any agent — swap --agent for codex, cursor, copilot.
Weekly change comes from our own snapshots, not the repository page — it measures attention, not adoption.
# Combinatorics Calculator Skill ## Purpose Calculate combinatorial values with modular arithmetic support for competitive programming applications. ## Capabilities - Factorial and inverse factorial precomputation - nCr, nPr with modular arithmetic - Catalan, Stirling, Bell numbers - Lucas theorem implementation - Inclusion-exclusion principle application - Generating functions ## Target Processes - combinatorics-counting - number-theory-algorithms - dp-pattern-matching ## Combinatorial Functions ### Basic Counting - Factorial: n! - Permutations: P(n,r) = n!/(n-r)! - Combinations: C(n,r) = n!/(r!(n-r)!) ### Special Numbers - Catalan numbers - Stirling numbers (first and second kind) - Bell numbers - Derangements ### Advanced Techniques - Lucas theorem (for large n, small p) - Inclusion-exclusion - Burnside's lemma - Generating functions ## Input Schema ```json { "type": "object", "properties": { "operation": { "type": "string", "enum": ["nCr", "nPr", "factorial", "catalan", "stirling", "lucas", "precompute"] }, "n": { "type": "integer" }, "r": { "type": "integer" }, "mod": { "type": "integer" }, "precomputeLimit": { "type": "integer" } }, "required": ["operation"] } ``` ## Output S
- Purpose
- Capabilities
- Target Processes
- Combinatorial Functions
- Basic Counting
- Special Numbers
- Advanced Techniques
- Input Schema
- Output Schema
What does the combinatorics-calculator skill do?
Calculate combinatorial values with modular arithmetic
How do I install it?
Run `npx skills add a5c-ai/babysitter --skill combinatorics-calculator --agent claude-code` — it drops the skill into your project so the agent can pick it up. Swap the --agent value for codex, cursor or copilot if you use one of those.
Where does this skill come from?
From a5c-ai/babysitter, a repository with 1,642 stars. We read it straight from the repository tree rather than a submitted listing, so what you see here is what is actually published.
Is a popular skill a good skill?
Not necessarily. Stars measure attention, not adoption — a repository can trend for a week and be abandoned. That is why we show the weekly change from our own snapshots next to the total, instead of a single flattering number.