## HBELABS.COM

 This is the 13,532-nd antisymmetric Dirichlet (136,519-th Dirichlet) eigenfunction in the (unit-edged) regular pentagon. It has about about 250 wavelengths across the pentagon. Its eigenvalue is about $\lambda=1,000,126.718$; which is the 81,917-th distinct Dirichlet eigenvalue. Click on it for a high resolution nodal pattern (20 pixels per wavelength).

### Personal Website of Bob Jones

Robert Stephen Jones
ORCID
rsjones7 at yahoo dot com
I am interested in calculating eigenvalues of the Laplacian for two-dimensional polygons, mostly for the regular pentagon. My project consists of two main parts. One is to calculate very many eigenvalues (over 160,000 of them) and the corresponding eigenfunctions, the other is to calculate very precise eigenvalues (at least 1000 digits).

ORCID: 0000-0003-3374-3540
My orcid.org QR:

### Play Boggle

Play boggle, the word game. This is me practicing server-side scripting in perl.

### Chinese-English Flashcard Program

FlashCard. Here is flashcard page I wrote featuring about 100,000 Chinese words. It is only used to help you visually memorize Chinese characters and compounds.

It is based on a corpus of 160,000 files (used to compute frequency) and an aging CEDICT (to provide the translations). The flashcard program uses an algorithm that I devised based entirely on my experience in using physical flashcards: It starts easy (most frequent) and progresses with spaced repetition.

You may optionally enter a string (not a password) that would be hard for someone to think of or guess, and then click [Start] (and then [Save] if asked). Use your string again if you want to resume where you left off. (Your string is displayed above the "card" in "FC: hbelabs→public→D95V", here it would be D95V.) While running it, click [Next] if you know the one with the definition displayed (and want it removed from your deck), click [Loop] if you want to put that one back in the deck. Every card shows up at least twice.

There are no logins or passwords, and there is no privacy or private information ... it is a flashcard program for fun. Everything is done server-side, there are no javascript, cookies, etc.