2222222222

Appears in sequences

• a(n) = 2*(10^n - 1)/9.at n=10A002276
• Repdigits (A010785), excluding repunits (A002275), ordered by product of digits (A007954).at n=36A070841
• A Jacobsthal sequence (A078008) to base 4.at n=21A092900
• Expansion of x*(1+x)/((1-x)*(1-10*x^2)).at n=20A094626
• Base 3 representation of the positive integers n such that Sum[d[k],k=1..n] is an integer, where d(k) is the base 3 fraction 0.k (e.g., d(22 base 10)=d(211 base 3)=0.221 base 3).at n=12A107483
• a(n)*n = A112893(n).at n=9A112894
• Smallest positive number divisible by n whose decimal expansion has the form 22...200...0.at n=10A216812
• Numbers n such that the cardinality of (natural numbers <=n with a first digit of 1) = n/2.at n=18A228158
• Repdigit numbers n such that the repeated digit of n is equal to the digital root of n.at n=23A271569
• Expansion of x*(1 + 2*x + 10*x^2)/((1 - x^2)*(1 - 10*x^2)).at n=20A322925
• Repdigit numbers (A010785) in A157037.at n=10A353704
• 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=44A376856