A bijection between symmetric plane partitions and quasi transpose complementary plane partitions
Takuya Inoue
TL;DR
The paper resolves the explicit bijection between $SPP(n;M)$ and $QTCPP(n;M)$ by linking Proctor’s parallel equinumerosities for $SPP$, $e$-SPP, stair-PP, and p-stair-PP to a signed-bijection framework. The core approach uses 1:2^{|S|} correspondences, non-intersecting lattice-path configurations, and the Lindström–Gessel–Viennot lemma, organized through the index sets $I_m$ and $J_m$ to pair staircase and even SPP decompositions. The main result is an explicit sijection, hence an explicit bijection between $SPP(n;M)$ and $QTCPP(n;M)$, resolving a 35-year open problem and enriching the combinatorial toolkit with signed-bijections and path-transform techniques. The framework also suggests connections to Pfaffian evaluations and provides a blueprint for extending bijections to other symmetry classes and parity-restricted partitions.
Abstract
We resolve the explicit bijection problem between symmetric plane partitions (SPPs) and quasi transpose complementary plane partitions (QTCPPs), introduced by Schreier-Aigner, who proved their equinumerosity. First, we relate this problem to Proctor's parallel equinumerosities for SPPs, even SPPs, staircase plane partitions, and parity staircase plane partitions, by constructing several bijections. As a result, we reduce the task to constructing a compatible bijection between even SPPs and staircase plane partitions. We then provide non-intersecting lattice path configurations for these objects, apply the LGV lemma, and transform the resulting path configurations. This process leads us to new combinatorial objects, $I_m$ and $J_m$, and the task is further reduced to constructing a compatible sijection (signed bijection) between $I_m$ and $J_m$, which is carried out in the final part of this paper. Our construction also answers the 35-year-old open problem posed by Proctor: constructing an explicit bijection between even SPPs and staircase plane partitions.
