191191

Appears in sequences

• Lucky numbers that are concatenations of a number k with itself.at n=24A032650
• Number of nonempty subsets of {1,2,...,n} in which exactly 1/5 of the elements are <= (n-2)/2.at n=24A047187
• Dates after Jan 01 00 in chronological order which are palindromic when they are written in the format DD.MM.YY. The terms are listed as numbers (without the dots). Leading zeros of the terms are suppressed.at n=28A210888
• Palindromes p = A002113(n) whose index n is a substring of p.at n=19A248753
• Palindromes that are multiples of 11 and whose digit sum is also a multiple of 11.at n=24A346221
• a(n) = Sum_{k=0..floor(2*n/5)} binomial(k+2,2) * binomial(k,2*n-5*k).at n=36A392270
• a(n) = Sum_{k=0..floor(3*n/5)} binomial(k+2,2) * binomial(k,3*n-5*k).at n=24A392314