Lemma
MediumCounting
#895 · Combinatorics · Counting

Permutations of "series"

How many distinct permutations can be formed from the letters of the word *series* when three letters are taken together as a block?

~3 minAnswer checked instantlyblock methodarrangements

H. S. Hall & S. R. Knight, Higher Algebra (1891) · Ch. XI. Permutations and Combinations, Examples XI.b, No. 23

Stuck? A gentle nudge
Something off?
Workspace
Your answer
Loading the math keyboard…

Type naturally — sqrt, pi, / and ^ become notation. Any equivalent form is accepted. Press Enter to check.