WORKED DEFAULT
Check the calculation with the default inputs
The integer 8 has five unordered partitions into exactly three positive parts.
- Fix totaln=8
- Fix part countk=3
- Count5 partitions
PARTITIONS / EXACT PART COUNT
Count unordered additive partitions of n containing exactly k positive integer parts.
METHOD / WORKED EXAMPLE
Count unordered additive partitions of n containing exactly k positive integer parts. The result panel keeps the defining recurrence or counting identity visible so the output can be checked independently.
WORKED DEFAULT
The integer 8 has five unordered partitions into exactly three positive parts.
READ THE RESULT
This fixes the number of parts, unlike the all-partition total or ordered composition counts.
ASSUMPTIONS AND LIMITS
The tool counts structures only and does not enumerate or sample the partitions.
COMMON QUESTIONS
Build exact-part counts from the empty partition, adding positive part sizes without distinguishing rearrangements. The indexing, equivalence relation, and counted objects are stated in the method and worked example. Inputs must be whole numbers inside the displayed domain; the page never rounds a decimal into an accepted index. This ties the answer to one explicit convention instead of silently mixing sequence offsets or combinatorial interpretations.
This fixes the number of parts, unlike the all-partition total or ordered composition counts. Small boundary cases and the displayed recurrence or identity provide useful independent checks. Recompute the displayed recurrence or closed form with the same inputs and compare its previous terms or counting factors. That check supports this bounded result, but it does not transfer the interpretation to a different sequence or counting object.
The tool counts structures only and does not enumerate or sample the partitions. The implementation uses integer arithmetic internally and refuses results beyond the safe display boundary. Combinatorial and recurrence values can grow rapidly even when the inputs look small. The conservative cap prevents browser stalls and avoids presenting an unsafe floating-point integer as exact; larger work needs arbitrary-precision software and independent resource controls.
RELATED TOOLS
Use boundary
Build exact-part counts from the empty partition, adding positive part sizes without distinguishing rearrangements.
P(n,k)=P(n-1,k-1)+P(n-k,k).