999999999999
domain: N
Appears in sequences
- a(n) = 10^n - 1.at n=12A002283
- Palindromes of form k*(k+2); or palindromes 1 less than a square.at n=27A028504
- Palindromic Super-9 Numbers.at n=4A032757
- Largest number whose square has n digits.at n=23A049416
- Continued fraction for Liouville's number (A012245).at n=7A058304
- Continued fraction for Liouville's number (A012245).at n=24A058304
- a(n) is the smallest number k such that the letter "N" appears n times when k is written in English.at n=30A060227
- Palindromes of the form k^3-1.at n=6A062841
- Palindromes k such that k + 2 is also a palindrome.at n=18A082274
- Palindromes arising in A083457.at n=11A083461
- Largest n-digit multiple of the n-th prime.at n=11A091801
- a(n) = 100^n - 1.at n=6A098609
- a(n) = 10^n - (-1)^n.at n=12A098611
- Inventory application: Numerator of the probability (rounded to the nearest trillionth: (10^-12)-th) of at least one shortage per month when n customers each request one item on one independently-chosen random day of a 30-day month, but when only exactly one such item is available per day.at n=30A099600
- a(n) = 0^n + 10^n - 1.at n=12A103456
- a(n) is the least positive integer in base 10 containing n nines that is divisible by n.at n=10A112909
- n times n+4 gives the concatenation of two numbers m and m-4.at n=18A116260
- Least concatenation of n to have exactly n prime factors with multiplicity.at n=8A118133
- a(n) = n^12 - 1.at n=9A123868
- Repdigit Kaprekar numbers.at n=19A145875