MathDB

There is a row that consists of digits from

0

9

and Ukrainian letters (there are

33

of them) with following properties: there aren’t two distinct digits or letters

a_i

a_j

such that

a_i > a_j

and

i < j

(if

a_i

a_j

are letters

a_i > a_j

means that

a_i

has greater then

a_j

position in alphabet) and there aren’t two equal consecutive symbols or two equal symbols having exactly one symbol between them. Find the greatest possible number of symbols in such row.

Problem Statement