Welcome to The Trillia Group
• Basic Concepts of Mathematics
• Mathematical Analysis I
• Mathematical Analysis II
• An Introduction to the Theory of Numbers
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About Trillia

About The Trillia Group

Our Goal

The Trillia Group's goal is to provide quality texts distributed at the lowest cost to the widest audience. To this end, we distribute the texts electronically and offer a free license for students using the texts for self-study and for teachers evaluating the text for use as a required or recommended text in a course. We offer colleges and universities generous terms to license the use of texts for all students and staff, now and in the future.


The Trillia Group accepts donations from people who support our goals. Donations of as little as US$2 or €2 help us continue to produce and distribute quality online texts.

Trillia's Economic Model, or, Why Our Books are not Free for All

Publishing is a large, multi-layered business, with authors and translators, their agents, publishers, sales agents, printers, distributors, national retailers, specialty retailers (of interest to us are university bookstores), and small local booksellers. Each layer in this business promotes the business as a whole, and takes its cut of the proceeds. In the end, textbooks for college classes end up costing $120. The university bookstores have tried to cut out some of the layers by buying "used" books for one-third the retail price and reselling them for 80% of retail. The publishers have retaliated by coming out with new editions of books every few years with minimal or trivial changes solely to kill this used-book market. Students feed this textbook economy.

The Trillia Group dramatically reduces the number of layers, acting as the sole intermediary between the author and you. Yes, we still have costs: technical typists, copy editors, copyright registration fees, fees for ISBN numbers, monthly fees for a web site, and, most importantly, royalties to authors. That's why there's still an intermediary between you and the author: to turn a typewritten manuscript with handwritten symbols and figures into a quality electronic text with a proper index, and to distribute it around the world. We charge for our texts to cover our costs and to enable the preparation of new texts.

Trillia in the Press

The efforts of The Trillia Group to distribute quality, affordable, texts online have been noted by the San Jose Mercury News and the Purdue Exponent, both in a news story and editorially.

Contact Us

Our products are described here. For other inquiries, please contact us at info@trillia.com. To suggest mathematical or typographical corrections to our products, please contact Bradley Lucier at Purdue University.

About Our Name

Trillia is the plural of trillium, the name of a family of flowers with three petals. The white trillium has been the floral emblem of the Province of Ontario, Canada, since 1937.

Copyright © 2001-2016 by The Trillia Group.
The phrase "The Trillia Group" and The Trillia Group logo are trademarks of The Trillia Group.
The Trillia Group participates in the eGranary Digital Library initiative of the WiderNet Project.