990000
domain: N
Appears in sequences
- 10^n-10^(n-2).at n=6A105694
- n and pi(n) are both made of nontrivial runs of identical digits, where pi(n)=A000720(n).at n=6A116056
- a(n) = n^6 - n^4.at n=10A136038
- Numbers k such that k and k^2 use only the digits 0, 1, 5, 8 and 9.at n=48A136874
- Numbers k such that k and k^2 use only the digits 0, 1, 6, 8 and 9.at n=52A136879
- Numbers k such that k and k^2 use only the digits 0, 1, 8 and 9.at n=48A136881
- Averages of twin prime pairs k such that k*11 and k/11 are squares.at n=0A154674
- Integers of the form k = m^3-m^2 such that k-+1 are primes.at n=11A154731
- The largest n-digit number whose last k digits are divisible by k^2 for k = 1..n, otherwise 0.at n=5A228011
- a(n) = n^2 with each digit repeated.at n=29A248126
- Numbers m such that the largest digit in the decimal expansion of 1/m is 1.at n=34A333402
- a(n) = phi(10^n+1), where phi is Euler's totient function (A000010).at n=6A366669