654321

Appears in sequences

• Concatenation of numbers from n down to 1.at n=5A000422
• Number of zeros in numbers 1 to 111...1 (n+1 digits).at n=5A014925
• n written in fractional base 7/6.at n=36A024643
• Append n to the previous term, reverse alternate terms.at n=5A053052
• Add (n mod 10)*10^(n-1) to the previous term, with a(0) = 0.at n=6A057138
• String together the first n numbers in an order which maximizes the result.at n=5A060554
• Dealing cards in a game of solitaire.at n=21A071761
• Triangle read by rows: the n-th row contains n numbers sorted in decreasing value, each build by dropping a different number from the sequence [n,n-1,n-2,....,1] and concatenating the n-1 others. By definition the first row contains 0.at n=27A081541
• Concatenation of digits of natural numbers from n down to 1.at n=5A104759
• Numbers with 6 distinct digits {1,2,3,4,5,6} such that all adjacent digits (as well as first and last digits) are coprime.at n=23A104973
• Integers written in base "triangle".at n=21A110301
• Largest composite number obtained by concatenation of parts of a distinct partition of n, or 0 if no such number exist.at n=20A110454
• a(n) = 1 + 2*n + 3*n^2 + 4*n^3 + 5*n^4 + 6*n^5.at n=10A113531
• Semiprimes with consecutive digits.at n=19A118697
• Factorial codes for the fixed points of the square of Vaillé's 1997 bijection on Dyck paths.at n=14A126299
• Nonnegative numbers with digits in descending order that differ exactly by 1.at n=41A138142
• a(n) = concatenation of reversed digits of natural numbers from n down to 1.at n=5A138793
• Reverse (palindrome) of A164844.at n=33A168647
• Semiprimes with digits in descending order that differ exactly by 1.at n=12A215478
• Given a number n with k digits d_i, enumerate the positions of the digits starting from LSD = 1 to MSD = k. Sequence lists the numbers such that Sum_{i=1..k} d_i/i and Sum_{i=1..k} i/d_i are equal and integer.at n=14A260487