1234554321

Appears in sequences

• Concatenation of sequence (1, 2, ..., floor((n-1)/2), floor(n/2), floor(n/2)-1, ..., 1) for n >= 1.at n=9A007907
• Number generated by regarding the numbers in row n of A003983 as digits of a base n number.at n=9A157452
• Concatenation of the numbers from 1 to n with numbers from n down to 1.at n=4A259937
• The concatenation of 123456...n and the reverse of this number.at n=4A261138
• Multiplication of pair of contiguous repunits, i.e., (0*1, 1*11, 11*111, 111*1111, 1111*11111, ...).at n=5A274766