MathDB
Purple Comet 2017 HS problem 7

Source:

March 19, 2020
combinatorics

Problem Statement

Consider an alphabetized list of all the arrangements of the letters in the word BETWEEN. Then BEEENTW would be in position 11 in the list, BEEENWT would be in position 22 in the list, and so forth. Find the position that BETWEEN would be in the list.