21800

Appears in sequences

• Percolation series for directed square lattice.at n=23A006462
• Number of partitions satisfying cn(0,5) + cn(1,5) + cn(4,5) <= cn(2,5) + cn(3,5).at n=42A039878
• Number of rooted 2-dimensional polyominoes with n square cells, with no symmetries removed.at n=7A048664
• Array read by antidiagonals: T(n,k) = number of rooted n-dimensional polycubes with k cells, with no symmetries removed (n >= 1, k >= 1).at n=43A048790
• Numbers n such that phi(n) is the sum of the first k divisors of n for some k.at n=21A072278
• Array read by antidiagonals: T(n,k) = number of rooted 2-dimensional polyominoes with k cells, the cells being regular n-gons, with no symmetries removed.at n=43A094166
• a(n) = Sum_{k=1..n} k*(prime(k) - k).at n=23A110477
• Irregular table whose rows list the nontrivial cycles of the ghost iteration A329201, starting with the smallest member.at n=8A329342
• Total sum of parts which are powers of 2 in all partitions of n.at n=25A342231