yaworsw/euler-manager

---
:id: 158
:name: Exploring strings for which only one character comes lexicographically after
  its neighbour to the left
:url: https://projecteuler.net/problem=158
:content: "Taking three different letters from the 26 letters of the alphabet, character
  strings of length three can be formed.  \nExamples are 'abc', 'hat' and 'zyx'.  \nWhen
  we study these three examples we see that for 'abc' two characters come lexicographically
  after its neighbour to the left.  \n For 'hat' there is exactly one character that
  comes lexicographically after its neighbour to the left. For 'zyx' there are zero
  characters that come lexicographically after its neighbour to the left.  \nIn all
  there are 10400 strings of length 3 for which exactly one character comes lexicographically
  after its neighbour to the left.\n\nWe now consider strings of <var>n</var> ≤ 26
  different characters from the alphabet.  \n For every <var>n</var>, p(<var>n</var>)
  is the number of strings of length <var>n</var> for which exactly one character
  comes lexicographically after its neighbour to the left.\n\nWhat is the maximum
  value of p(<var>n</var>)?\n\n"