# OCME · Knowledge & practice explorer

302 MKO / 1,441 families / 360 batches / 36,000 questions.

36,000 second-context math/bilingual reviewed; 0 display/symbol-checked candidates. Source questions: candidate. English: ai_candidate. No new proof, Lean, SREG or training.

1 results; page 1/1.

## Question 20920: All Nonempty Index Subsets Are Needed for the Exact Alternating Sum

- ID: `q-20261014-advance-20261108-r05-inclusion-exclusion-principle-0070`; number: 20920
- Processing: second_context_reviewed
- MKO: [mko-inclusion-exclusion-principle](/en/mko/mko-inclusion-exclusion-principle/)
- Family: [qf-mod39-incexc-general-alternating-sum](/en/explore/?family=qf-mod39-incexc-general-alternating-sum)
- Batch: [batch-20261014-advance-20261108-r05-inclusion-exclusion-principle-foundations](/en/explore/?batch=batch-20261014-advance-20261108-r05-inclusion-exclusion-principle-foundations)
- [Derivation](/en/questions/q-20261014-advance-20261108-r05-inclusion-exclusion-principle-0070/) / [Markdown](/en/questions/q-20261014-advance-20261108-r05-inclusion-exclusion-principle-0070/index.md) / [JSON](/data/question-derivations/questions/q-20261014-advance-20261108-r05-inclusion-exclusion-principle-0070.json)