Error message

Deprecated function: Optional parameter $js declared before required parameter $element is implicitly treated as a required parameter in include_once() (line 1445 of /var/www/html/mathtube.org/includes/bootstrap.inc).
Deprecated function: Optional parameter $input declared before required parameter $form_state is implicitly treated as a required parameter in include_once() (line 1445 of /var/www/html/mathtube.org/includes/bootstrap.inc).

Noam Elkies

Title	Conference	Date
Crossing Numbers of Large Complete Graphs (Video)	The Unsolved Problems Conference: Celebrating the living legacy of the mathematics of Richard Guy	Oct 2, 2020