22222222

Appears in sequences

• a(n) = 2*(10^n - 1)/9.at n=8A002276
• Repdigit + 1 is prime.at n=9A028988
• Digital representation of m contains only either 1's or 2's (but not both 1's and 2's) and 0's, is palindromic and contains no singleton 2's, 1's or 0's.at n=21A061852
• a(n) is the largest number whose product of decimal digits equals n^n.at n=2A068186
• Repdigits (A010785), excluding repunits (A002275), ordered by product of digits (A007954).at n=28A070841
• Quadruplets: base 10 representation is the juxtaposition of four identical strings.at n=21A074843
• Squarefree numbers obtained by repeating a single digit.at n=38A077571
• Palindromes p such that 5p + 1 is also a palindrome.at n=22A083833
• A Jacobsthal sequence (A078008) to base 4.at n=17A092900
• Expansion of x*(1+x)/((1-x)*(1-10*x^2)).at n=16A094626
• Longest sequence of distinct integers such that the length of the n-th term is given by the n-th digit of the sequence itself.at n=18A108718
• Consider the Levenshtein distance between k considered as a decimal string and k considered as a binary string. Then a(n) is the least number m such that the Levenshtein distance is n or 0 if no such number exists.at n=25A115778
• The smallest number that has more copies of some digit than all previous terms of the sequence put together.at n=29A179310
• List of imprimitive words over the alphabet {2,3}.at n=22A213974
• Numbers n such that the cardinality of (natural numbers <=n with a first digit of 1) = n/2.at n=14A228158
• Expansion of x*(1 + 2*x + 10*x^2)/((1 - x^2)*(1 - 10*x^2)).at n=16A322925
• a(1) = 1; for n > 1, a(n) is the smallest unused positive number such that a(n), |a(n) - a(n-1)| and a(1) + ... +a(n) are all palindromes.at n=34A376856
• Happy repdigit numbers.at n=8A381046