66666

Appears in sequences

• a(n) = 6*(10^n - 1)/9.at n=5A002280
• Repdigit numbers, or numbers whose digits are all equal.at n=42A010785
• Numbers > 9 with all digits the same.at n=32A014181
• a(n) = floor(10^6/n).at n=14A033426
• Write what is described (putting a leading zero on numbers which have an odd number of digits).at n=56A056967
• Numbers n such that n and 2n-1 are both palindromes.at n=9A069882
• Worthless numbers: numbers without h, o, r, t, or w.at n=6A073419
• Number of Fibonacci numbers F(k), k <= 10^n, which end in 2.at n=5A073548
• Number of Fibonacci numbers F(k), k <= 10^n, which end in 6.at n=5A073549
• Squarefree numbers obtained by repeating a single digit.at n=26A077571
• Smallest multiple of n using only digits 0 and 6.at n=40A078245
• Sum of the forward and reverse concatenations of 1 to n.at n=4A078262
• a(n) = A084006(n)^(1/2).at n=12A084007
• Number of configurations of a variant of the 3-dimensional 3 X 3 X 3 sliding cube puzzle that require a minimum of n moves to be reached, starting with the empty space at one of the enclosing cube corners.at n=11A090577
• Triangle read by rows: T(n,k) = (n+1,k)-th element of (M^10-M)/9, where M is the infinite lower Pascal's triangle matrix, 1<=k<=n.at n=16A096044
• Largest term in periodic part of continued fraction expansion of square root of n-th repunit.at n=9A096487
• Numbers m such that phi(m) = d_1*d_1!+d_2*d_2!+...+d_k*d_k! where d_1 d_2 ... d_k is the decimal expansion of m.at n=2A101699
• Berend Jan van der Zwaag's conjectured complete list of numbers that start different "expanding periodic loops" under the mapping described in A053392 and A060630.at n=20A103117
• a(n)*n = A112895(n).at n=4A112896
• Result of left concatenation of the next Roman-numeral symbol.at n=9A118640