Dynamic

https://toto-school.ru/raznoe-2/modeli-dinamicheskih-sistem-primery-modelirovanie-dinamicheskih-sistem-vvedenie-habr.html#i

E, pi

https://ilyabirman.ru/meanwhile/all/pi-and-e/

Mad, Stdev

https://towardsdatascience.com/why-is-the-mad-always-smaller-than-the-std-77c7fcee80a4

https://studizba.com/lectures/matematika/statisticheskie-metody-eksperimentalnyh-issledovaniy/13033-mery-centra-i-razbrosa.html