This paper develops twin models towards integrated production inventory planning for manufacturer–retailer ecosystem in a sustainable supply chain setup. Decision-making models are developed in fuzzy environment and under purview of carbon taxation system. Novel conception of Fermatean fuzzy numbers is introduced for handling parameters imprecision. The first model addresses planning problem without considering green investments, whereas the second one additionally identifies optimal green investments for each player of ecosystem. Models are formulated as nonlinear optimization problems with objective of maximizing profit. Comparison of results from both models enables decision-makers to figure out the profitability of green investment option. Numerical instance with data from the existing literature is solved using Mathematica 12.1. Computational results for studied case report profitability of green investments for supply chain partners and significant reduction in carbon emissions as well. Variation analysis demonstrates stability of the proposed model. Developed models equip small-scale retailer-manufacture tie-ups prevalent in developing economies for discussed decisions.

本文针对可持续供应链设置中制造商-零售商生态系统的集成生产库存规划开发了双模型。决策模型是在模糊环境和碳税系统范围内开发的。引入费马模糊数的新概念来处理参数的不精确性。第一个模型在不考虑绿色投资的情况下解决规划问题，而第二个模型另外为生态系统的每个参与者确定最佳绿色投资。模型被表述为以利润最大化为目标的非线性优化问题。比较两种模型的结果使决策者能够计算出绿色投资方案的盈利能力。使用 Mathematica 12.1 解决了现有文献中数据的数值实例。研究案例的计算结果报告了供应链合作伙伴绿色投资的盈利能力以及碳排放量的显着减少。变异分析证明了所提出模型的稳定性。发达的模型为发展中经济体普遍存在的小型零售商-制造商合作提供了讨论决策的条件。