** Markov chains
*** Probleme: 'Humpty Dumpty':http://acm.timus.ru/problem.aspx?space=1&num=1766, 'Random Run':http://codeforces.com/problemset/gymProblem/101081/B
* 'Principiul includerii si excluderii':principiul-includerii-si-excluderii

** Probleme: 'cowfood':problema/cowfood, 'indep':problema/indep, 'frac':problema/frac, 'CF 451E':http://codeforces.com/contest/451/problem/E, 'light2':problema/light2, 'trickortreat':problema/trickortreat

** Probleme: 'cowfood':problema/cowfood, 'indep':problema/indep, 'frac':problema/frac, 'CF 451E':http://codeforces.com/contest/451/problem/E, 'light2':problema/light2, 'trickortreat':varena.ro/problema/trickortreat

* 'Lema lui Abel':https://en.wikipedia.org/wiki/Summation_by_parts
** Probleme: 'Power of Power Partition Function':http://opencup.ru/files/och/gp11/problems1-e.pdf
* 'Taylor series':https://en.wikipedia.org/wiki/Taylor_series