[LM24] OK, So What Do We Talk About Between Last Year's Le Mans and Next Year's.....?

[clkgtrlm1]

Originally Posted by RL17

A few connected years/numbers at Le Mans questions.

Just 5 questions and Questions only cover 1st 5 occurances in the sequence (as some of the occurrances really start to ramp up in 1980's onwards).

And apologies if most things nearly always start in 1923 (as they do) and it is a bit of a quiet time with week or so before ticketing opens.

What's the missing year/number in the sequence and why?

1. 1923, 1968, 2020, 2021?

2. 1923, 1931, 1967 ? (only 4 years in this sequence/series)

3. 1923, 1924, 1952, 1966?

4. 12, 13, 25, 26?

5. 1923, 1926, 1962, 1982?

I can only get the first 2.

1/ 1956?
2/ 1953?