A function that satisfies both $f(x+1)=f(x)+1$ and $f(x^2)=f(x)^2$ for all real $x$ is known to be the identity over $\mathbb Q$, but is it also the identity over $\mathbb R$? If not, can you provide me an example of such a function? Thanks.
(Answered for future reference)
It looks like the browser is caching a wrong version of MathJax. Try to clear the browser cache by holding Shift and click Refresh.
"The Book of Sand" (original Spanish title: "El libro de arena") is a 1975 short story by Jorge Luis Borges. It has parallels to "The Zahir", continuing the theme of self-reference and attempting to abandon the terribly infinite.
The story appears in a book of the same name, the Spanish language version of which was first published in 1975. The English translation by Norman Thomas di Giovanni was first published in The New Yorker; the entire volume The Book of Sand (ISBN 0-525-47540-0) was published in 1977.
Plot summary
The titular "Book of Sand" is the Book of all Books, and is a m...
