999999999
domain: N
Appears in sequences
- Concatenate n n times.at n=8A000461
- a(n) = 10^n - 1.at n=9A002283
- Divisors of 999999999.at n=19A027889
- Numbers k such that k*(k+2) is a palindrome.at n=37A028503
- a(n) = (n+1)^n - 1.at n=9A037205
- Numbers with digits nondecreasing and their reciprocals sum to 1/(positive integer).at n=50A045910
- Replace each 1 in decimal expansion of n with 1 1's, each 2 with 2 2's, etc. (0 vanishes).at n=8A048376
- Largest number whose square has n digits.at n=17A049416
- n times (n 1's): a(n) = n*(10^n - 1)/9.at n=9A053422
- Largest number that has the same number of digits in base 10 and base n, or 0 if no such number exists.at n=11A055866
- Duplicate of A037205.at n=9A060071
- a(n) is the smallest number k such that the letter "N" appears n times when k is written in English.at n=22A060227
- Smallest number whose sum of digits is n^4.at n=2A060711
- Smallest number whose sum of digits is 3^n.at n=4A060712
- Smallest number whose sum of digits is n^2.at n=9A061104
- Largest number whose cube has n digits.at n=26A061439
- Palindromes of the form k^3-1.at n=5A062841
- Largest n-digit multiple of n.at n=8A066557
- a(n) = A066557(n)/n.at n=9A066558
- a(n) is the smallest number such that the product of its decimal digits equals n^n, or 0 if no solutions exist.at n=8A068187