Sure, here are a few luxury apartment complexes in Lucknow offering 3-6 BHK flats along with some information about them:

Virasat Udai Grand: Virasat Udai Grand is a premium residential project located in  Vipul Khand, Gomti Nagar, Lucknow. It offers spacious 3, 4, 5, and 6 BHK apartments with modern amenities like a swimming pool, gymnasium, landscaped gardens, clubhouse, and more. The project is developed by Eldeco Group, known for its quality construction and timely delivery.

Eldeco Regalia: Eldeco Regalia is a premium residential project located in Vibhuti Khand, Gomti Nagar, Lucknow. It offers spacious 3, 4, 5, and 6 BHK apartments with modern amenities like a swimming pool, gymnasium, landscaped gardens, clubhouse, and more. The project is developed by Eldeco Group, known for its quality construction and timely delivery.

Rishita Mulberry Heights: Situated in Sushant Golf City, Lucknow, Rishita Mulberry Heights is a luxurious residential project offering 3, 4, 5, and 6 BHK apartments. The project boasts of lavish interiors, premium fittings, and a range of amenities including a clubhouse, swimming pool, jogging track, and landscaped gardens. It is developed by Rishita Developers, known for their commitment to quality and customer satisfaction.

Omaxe Hazratganj Residency: Omaxe Hazratganj Residency is a high-end residential project located in Hazratganj, Lucknow. It offers spacious 3, 4, 5, and 6 BHK apartments with modern amenities such as a clubhouse, swimming pool, gymnasium, and lush green surroundings. The project is developed by Omaxe Ltd, one of India's leading real estate developers with a strong track record of delivering quality projects.

Experion Capital: Experion Capital is a luxury residential project situated in Gomti Nagar, Lucknow. It offers spacious 3, 4, 5, and 6 BHK apartments with contemporary designs and premium finishes. The project features amenities like a clubhouse, swimming pool, landscaped gardens, and sports facilities. Developed by Experion Developers, the project focuses on providing a luxurious lifestyle experience to its residents.

Paarth Aadyant: Located in Gomti Nagar Extension, Lucknow, Paarth Aadyant is a premium residential project offering 3, 4, 5, and 6 BHK apartments. The project is designed to provide a modern and luxurious living experience with amenities such as a clubhouse, swimming pool, fitness center, landscaped gardens, and more. It is developed by Paarth Infrabuild, a reputed real estate developer known for its quality construction and innovative designs.

These are just a few examples of luxury apartment complexes in Lucknow offering 3-6 BHK flats. Each of these projects offers a unique blend of luxury, comfort, and convenience to cater to the needs of discerning homebuyers.