Question: The Red Jinn, later known as Jinnicky, is one of Ruth Plumly Thompson's most frequently occurring characters in her Oz books, he was reintroduced, drawn, and given the name Jinnicky in "The Purple Prince of Oz"; he also appeared in which follow-up, the thirty-second of the Oz books created by L. Frank Baum and his successors, and the eighteenth written by Ruth Plumly Thompson?
Context: Grampa in Oz (1924) is the eighteenth in the series of Oz books created by L. Frank Baum and his successors, and the fourth written by Ruth Plumly Thompson. The Enchanted Island of Oz is a children's novel written by Ruth Plumly Thompson and illustrated by Dick Martin, and first published in 1976.  As its title indicates, the book is an entry in the series of Oz books created by L. Frank Baum and his successors.  It is the last (and shortest) of Thompson's 21 novels about the Land of Oz. The Gnome King of Oz (1927) is the twenty-first in the series of Oz books created by L. Frank Baum and his successors, and the seventh by Ruth Plumly Thompson.  Like nineteen of the twenty previous books, it was illustrated by John R. Neill. This is a list of characters in the original sequel Oz books by American author L. Frank Baum, and in the later continued Oz series by his grandson Roger S. Baum, Ruth Plumly Thompson, John R. Neill, Jack Snow, Rachel Cosgrove Payes, Eloise Jarvis McGraw and Lauren McGraw, Dick Martin, Eric Shanower, and Sherwood Smith.  Characters from Gregory Maguire's "Wicked" are not included, as his works, among others such as the work of March Laumer, are considered "heretical" in Baum scholarship (The term "heretical" was first applied to these books by Dr. Stephen J. Teller of Pittsburg State University in the Winter 1988 issue of "The Baum Bugle" and appears regularly in Oz fandom). The Purple Prince of Oz (1932) is the 26th in the series of Oz books created by L. Frank Baum and his successors, and the 12th written by Ruth Plumly Thompson.  It was illustrated by John R. Neill. The Royal Book of Oz (1921) is the fifteenth in the series of Oz books, and the first by Ruth Plumly Thompson, to be written after L. Frank Baum's death.  Although Baum was credited as the author, it was written entirely by Thompson.  Beginning in the 1980s, some editions have correctly credited Thompson, although the cover of the 2001 edition by Dover Publications credits only Baum.  The original introduction claimed that the book was based on notes by Baum, but this has been disproved.  Baum's surviving notes, known as "An Oz Book" are known from four typewritten pages found at his publisher's, but their authenticity as Baum's work has been disputed.  Even if genuine, they bear no resemblance to Thompson's book. The Red Jinn, later known as Jinnicky, is one of Ruth Plumly Thompson's most frequently occurring characters in her Oz books.  He was first introduced in "Jack Pumpkinhead of Oz" as a mysterious figure who educates Jack Pumpkinhead on the use of the Pirate Sack.  Although a detailed description is included in the text, "Jack Pumpkinhead of Oz" includes no illustrations of the Red Jinn aside from a gruesome color plate that did not appear outside the first edition, in which he has massive piercings.  He was reintroduced, drawn, and given the name Jinnicky in "The Purple Prince of Oz"; he also appeared in the follow-up, "The Silver Princess in Oz".  (He makes a cameo appearance in "The Wishing Horse of Oz", and he is the principal pre-existing character in Thompson's sub-canonical penultimate Oz book, "Yankee in Oz").  Jack Snow apparently thought the Red Jinn was a separate character, for he considered "The Purple Prince of Oz" Jinnicky's first appearance in "Who's Who in Oz", though he did not include a separate Red Jinn entry. This page is a supplement to List of Oz books featuring published books, often by small publishing houses.  Their canonicity is up to the individual reader, with some purists considering them apocryphal.  As the Baum Oz books are in the public domain, no clearance needs to be obtained to write and publish fiction about the Oz characters, professionally or otherwise, making the question of canonicity somewhat subjective.  Additionally, both of Jack Snow's Oz books are in the public domain in the United States, as are Ruth Plumly Thompson's "The Royal Book of Oz", "Kabumpo in Oz", "The Wishing Horse of Oz", "Captain Salt in Oz", "Handy Mandy in Oz", "The Silver Princess in Oz", and "Ozoplaning with the Wizard of Oz", making the distinctive elements in those books usable as public domain content.  The most dramatic changes in her books are in "The Lost King of Oz" and "The Giant Horse of Oz", both of which remain protected under U.S. copyright law, and has rendered some known manuscripts unpublishable.  The Oz books of John R. Neill, Rachel R. Cosgrove, and Eloise Jarvis McGraw and her daughter Lauren are all protected under U.S. copyright, making their characters and developments unusable by others without permission. The Silver Princess in Oz (1938) is the thirty-second of the Oz books created by L. Frank Baum and his successors, and the eighteenth written by Ruth Plumly Thompson.  It was illustrated by John R. Neill. The Wishing Horse of Oz (1935) is the twenty-ninth in the series of Oz books created by L. Frank Baum and his successors, and the fifteenth written by Ruth Plumly Thompson.  It was Illustrated by John R. Neill.  This book marked the point at which Thompson had written more Oz books than Baum himself.
Answer: The Silver Princess in Oz