6666667

Appears in sequences

• a(n)^2 is smallest square starting with a string of n 4's.at n=6A034984
• Numbers k such that k^2 contains only digits {4,8,9}.at n=14A053966
• Number of Fibonacci numbers A000045(k), k <= 10^n, which end in 4.at n=8A067275
• Duplicate of A067275.at n=8A073552
• Numbers k with the property that k divides one of the concatenations (k-1)(k-2) or (k-2)(k-1).at n=30A077292
• Numbers n > 2 such that n divides the concatenation of n-2 and n-1.at n=8A088797
• Centered hexamorphic numbers: the k-th centered hexagonal number, 3k(k-1)+1, ends in k.at n=36A094534
• Numbers k such that the k-th triangular number contains only digits {2,7,8}.at n=18A119179
• Numbers whose square starts with 7 identical digits.at n=8A133183
• Numbers k such that k and k^2 use only the digits 4, 6, 7, 8 and 9.at n=26A137145
• Numbers n such that the decimal representation of n is contained as substring in that of the n-th pentagonal number.at n=29A179782
• For k in {2,3,...,9} define a sequence as follows: a(0)=0; for n>=0, a(n+1)=a(n)+1, unless a(n) ends in k, in which case a(n+1) is obtained by replacing the last digit of a(n) with the digit(s) of k^2. This is k(8).at n=37A237345
• Numbers k such that k*(k-1) is composed of exactly two different decimal digits.at n=41A380974
• 3-automorphic numbers: positive integers k such that 3k^2 ends with k.at n=20A383821