12344321

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=7A007907
• All possible products in increasing order of two distinct members of the unary sequence 1, 11, 111, 1111, 11111, ...given by A000042.at n=15A077488
• Concatenation of the numbers from 1 to n with numbers from n down to 1.at n=3A259937
• The concatenation of 123456...n and the reverse of this number.at n=3A261138
• Multiplication of pair of contiguous repunits, i.e., (0*1, 1*11, 11*111, 111*1111, 1111*11111, ...).at n=4A274766
• Numbers that can be written as a product of distinct repunits.at n=18A334131