2221222

Appears in sequences

• k th digit of a(n) is the number of different digits within 3 of k (not including k).at n=31A039989
• k th digit of a(n) is the number of different digits within 4 of k (not including k).at n=28A039990
• Numbers n which in decimal have the form imj, where m is the middle digit, with property that j is the reversal of i, and i = m*j.at n=30A082945
• a(n) = 2*(10^(2n+1)-1)/9 - 10^n.at n=3A332121