Since 1≤a1<a2<⋯<a2022, we have ai≥i for all 1≤i≤2022. Also, the condition a12−62≥a22−72≥⋯≥a20222−20272 is equivalent to ai+12−ai2≤(i+6)2−(i+5)2=2i+11 (1≤i≤2021).
When ai+1≥ai+3 holds for some 1≤i≤2021, we have ai+12−ai2≥(ai+3)2−ai2=6ai+9≥6i+9>2i+11 for such i, which contradicts to ai+12−ai2≤2i+11. Therefore, since ai<ai+1, we have ai+1=ai+1 or ai+1=ai+2 (1≤∀i≤2021).
For each i, if ai+1=ai+1, then since ai+12−ai2=2ai+1, ai+12−ai2≤2i+11 is equivalent to ai≤i+5. Therefore, the tuples satisfying ai+1=ai+1 for all 1≤i≤2021 are of the form ai=i+c for a constant integer 0≤c≤5. There are exactly six such tuples.
Hereafter, we assume that ai+1=ai+2 for some 1≤i≤2021 and denote the maximum of such i by j. Since 4j+4≤4aj+4=aj+12−aj2≤2j+11, we have j=1,2,3.
* When j=1, since 4a1+4=a22−a12≤2⋅1+11, we have a1=1,2. In this case, (a1,a2,…,a2022)=(1,3,4,5,…,2022,2023), (2,4,5,6,…,2023,2024).
* When j=2, since 4a2+4=a32−a22≤2⋅2+11 and a2≥2, we have a2=2. In this case, (a1,a2,…,a2022)=(1,2,4,5,6,…,2022,2023).
* When j=3, since 4a3+4=a42−a32≤2⋅3+11 and a3≥3, we have a3=3. In this case, (a1,a2,…,a2022)=(1,2,3,5,6,7,…,2022,2023).
Hence the total number of the tuples is 6+4=10.