Gaps filled in
Every proof step says which hypothesis and which earlier result it uses. Nothing is left to “it is easy to see”.
Rikai
Textbooks for the LLM era — built from definitions, with no proof left out.
Why another textbook site
Section titled “Why another textbook site”When a textbook loses you, it is usually because of what it did not write: the three lines hidden behind “clearly”, the step that silently used an unstated hypothesis, the theorem whose purpose is never explained. Rikai writes those parts down.
Read it with an LLM
One button sends the whole article to your own Claude or ChatGPT account. Hover any formula to copy its LaTeX source.
The English edition is being translated from the Japanese one. The Japanese site currently has the full catalogue.
Operated by: Mugen Giken LLC ・Pricing ・Terms ・Legal notice