Is there any particular order to read Robert Lazarus Long series?

You're likely thinking about Robert A. Heinlein's "The Number of the Beast", which features the character Lazarus Long. This book is actually the *third* in a loosely connected trilogy, even though it was the first one published.

Here's the recommended reading order for the "Lazarus Long" series:

1. Time Enough for Love (1973): This is considered the "true" beginning of the series and introduces Lazarus Long, a man who has lived for centuries due to advanced technology.

2. The Number of the Beast (1980): This book picks up after "Time Enough for Love" and is set in a future where Lazarus is a powerful, centuries-old figure who is involved in various historical events and social commentary.

3. Methuselah's Children (1958): This book is set before the events of the other two and tells the origin story of Lazarus Long and the "Methuselah's Children," a group of individuals who have achieved near-immortality.

Important note: While these books form a trilogy, they are also part of the larger Heinlein universe, which can be explored in other works such as "Stranger in a Strange Land" and "Starship Troopers".

Enjoy reading Heinlein's fascinating and thought-provoking stories!