21339

Appears in sequences

• Trajectory of 18 under iteration of the map k -> A087712(k).at n=27A077960
• Isomers of polyenes attached to benzene (see Cyvin et al. for precise definition).at n=9A121097
• a(n) = 729*n - 531.at n=29A156771
• a(n) = Sum_{k<=n} A000203(k)*(n-k+1), where A000203(m) is the sum of divisors of m.at n=41A175254
• Number of 4-bead necklaces labeled with numbers -n..n allowing reversal, with sum zero with no three beads in a row equal.at n=30A209345
• Number of partitions p of n such that the number of parts is not a part and max(p) - min(p) is not a part.at n=39A241385
• Partial sums of A256970.at n=38A256971
• a(n) = f(n,n) where f(0,n) = f(n,0) = n! and f(m,n) = f(m-1,n) + f(m,n-1) + f(m-1,n-1).at n=6A346374
• Bitwise encoding of the state of a 1D cellular automaton after n steps from ...111000... where adjacent cells swap 01 <-> 10 when within triples 110 or 011.at n=29A359303