Harriongton Park, NJ — December 29, 2025 — We successfully solved the MIPLIB benchmark instance bley_xs1noM, achieving an objective value of 3,855,895.86 and proving the solution optimal with a 0.00% optimality gap using ODH|Xpress.

MIPLIB instances are widely used to benchmark mixed-integer optimization performance across a broad range of real-world problem structures. Achieving a provably optimal result on a benchmark model demonstrates both solution quality and the ability to certify optimality through rigorous branch-and-bound and cutting-plane methods.

“This result highlights our ability to deliver not only strong solutions, but also formal proof of optimality on challenging benchmark instances,” said Robert Asford, CEO. 

Result Summary

• Benchmark library: MIPLIB
• Instance: bley_xs1noM
• Link: https://miplib.zib.de/instance_details_bley_xs1noM.html
  
• Objective value: 3,855,895.86
• Optimality gap: 0.00% (proven optimal)
• Solver workflow: ODH|Xpress

About MIPLIB

MIPLIB is a widely used public benchmark library for mixed-integer programming, supporting transparent and repeatable evaluation of optimization methods across diverse problem classes.

Alkis Vazacopoulos, PhD
Mobile 201-256-7323
Skype alkiviadis1256
–––––
Optimization Direct, Inc.

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