444444444
domain: N
Appears in sequences
- a(n) = 4*(10^n - 1)/9.at n=9A002278
- Repdigit - 1 is prime.at n=11A028987
- Nonsquarefree numbers obtained by repeating a single digit.at n=32A077572
- Smallest multiple of n using only digits 0 and 4.at n=8A078243
- Smallest multiple of n using only digits 0 and 4.at n=17A078243
- Smallest multiple of n using only digits 0 and 4.at n=35A078243
- a(n) = A084006(n)^(1/2).at n=24A084007
- a(n) is the least positive integer in base 10 containing n fours that is divisible by n.at n=8A112897
- a(n) = 111111111 * n.at n=3A172525
- A109613(n)-fold concatenation of A008619(n).at n=7A180115
- In base 10 lunar arithmetic, a(n) is the smallest number than has exactly n different square roots (or -1 if no such number exists).at n=4A202174
- Repdigits which are also Harshad numbers.at n=21A377228