181818

Appears in sequences

• Numbers whose consecutive digits differ by 7.at n=30A048409
• Triplets: base 10 representation is the juxtaposition of three identical strings.at n=17A074842
• List of words over {1,8} with equal numbers of 1's and 8's.at n=13A214531
• Numbers n such that the result of n multiplied by the reversal of n can be split into two numbers a and b of equal length (if the length is odd a leading zero is allowed), where a + b equals n (b can also have a leading zero).at n=22A259316
• Terms of A338039 that are repeated concatenations of smaller integers.at n=2A338166