<p>This paper explores two families of integer partition functions, <i>Q</i>(<i>d</i>;&#xa0;<i>n</i>) and <i>P</i>(<i>d</i>;&#xa0;<i>n</i>), which count partitions of <i>n</i> under certain restrictions on how many times each part can appear. The first function, <i>Q</i>(<i>d</i>;&#xa0;<i>n</i>), counts partitions where no part shows up <i>d</i> or more times. The second, <i>P</i>(<i>d</i>;&#xa0;<i>n</i>), involves a signed count of partitions where the number of times each part appears is either 0 or 1 modulo <i>d</i>. These functions generalize some well-known partition types—like distinct partitions—and turn out to have a surprisingly rich structure. We prove a collection of identities that tie these two functions together. This includes convolution formulas, mutual expansions, and an orthogonality relation. We also find recurrences and develop exact formulas for both <i>Q</i>(<i>d</i>;&#xa0;<i>n</i>) and <i>P</i>(<i>d</i>;&#xa0;<i>n</i>) using sums over partitions. Altogether, these results reveal a deeper algebraic and combinatorial picture behind partitions with multiplicity constraints.</p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

Partitions with multiplicity constraints

  • Mircea Merca

摘要

This paper explores two families of integer partition functions, Q(dn) and P(dn), which count partitions of n under certain restrictions on how many times each part can appear. The first function, Q(dn), counts partitions where no part shows up d or more times. The second, P(dn), involves a signed count of partitions where the number of times each part appears is either 0 or 1 modulo d. These functions generalize some well-known partition types—like distinct partitions—and turn out to have a surprisingly rich structure. We prove a collection of identities that tie these two functions together. This includes convolution formulas, mutual expansions, and an orthogonality relation. We also find recurrences and develop exact formulas for both Q(dn) and P(dn) using sums over partitions. Altogether, these results reveal a deeper algebraic and combinatorial picture behind partitions with multiplicity constraints.