History of Pairs to Ten
A pen-and-paper puzzle from school exercise books; where it comes from is not documented.
From exercise books
Where the puzzle comes from is not documented in the sources PaperGames could check. A 2011 article on the Russian website Habr remembers it from school and university: it was played in squared exercise books, under names such as "numbers", "digits", "seeds" or "19" - there was no official name. There the game begins with the numbers 1 to 19 (without 10) written in a row, the same digits as the classic start here, and when no pair is left the remaining digits are copied at the end.
The name
"Pairs to Ten" simply says what the puzzle is about. Several apps play the same idea under names of their own; PaperGames does not use them. The diagonal pairs, the limit of 5 Adds and of 40 rows are PaperGames rules.