The Louvre Museum as seen through the Louvre Pyramid glass in Paris, France. From the National Geographic book The 10 Best of Everything. Smithsonian Institution, Washington, D.C. The Smithsonian is the worldâs largest research and museum complex, with 19 museums and galleries, the National Zoological Park, and various research stations.
1 An arithmetic sequence is a sequence with the difference between two consecutive terms constant. 2  The difference is called the common difference. 3  A geometric sequence is a sequence with the ratio between two consecutive terms constant. 4  This ratio is called the common ratio.
An arithmetic series is the sum of the terms of an arithmetic sequence. A geometric series is the sum of the terms of a geometric sequence. There are other types of series, but you're unlikely to work with them much until you're in calculus. For now, you'll probably mostly work with these two. This page explains and illustrates how to work with arithmetic series.