Sequences

Number of one-sided 4-dimensional polyominoes with n cells.

Number of one-sided, properly 5-dimensional polyominoes with n cells.

Number of strictly 2-dimensional fixed polyominoes with n cells.

Number of fixed properly-3-dimensional polyominoes with n cells.

Number of fixed properly-4-dimensional polyominoes with n cells.

Number of strictly 2-dimensional polyominoes with n cells.

Number of 3-dimensional polyominoes with n cells.

Number of 4-dimensional polyominoes with n cells.

Number of 5-dimensional polyominoes with n cells.

Elliptic divisibility sequence associated with elliptic curve "37a1": y^2 + y = x^3 - x and multiples of the point (0,0).

Number of fixed n-celled polyominoes which need only touch at corners.

Exponential self-convolution of numbers of trees on n nodes.

Sum of spans of 2n-step polygons on square lattice.

Sum of squared spans of 2n-step polygons on square lattice.

Number of 2n-step polygons on honeycomb.

Erroneous version of A309982.

Number of n-step spirals on hexagonal lattice.

Number of n-step spirals on hexagonal lattice.

Number of n-step spirals on hexagonal lattice.

Number of n-step spirals on cubic lattice.

Number of n-step anisotropic spirals on cubic lattice.

Number of polygons of length 4n on Manhattan lattice.

Number of polygons of length 4n on L-lattice.

Maximally extended polygons of length 2n on cubic lattice.

Engel expansion of Pi.

Number of triangle-free graphs on n vertices.

Number of squarefree graphs on n vertices.

Number of n-node graphs with no cycles of length less than 5.

a(n) = floor(2^(n-1)/n).

Bessel numbers: the number of nonoverlapping partitions of an n-set into equivalence classes.

Exponentiation of e.g.f. for trees A000055(n-1).

Number of cyclically-5-connected planar trivalent graphs with 2n nodes.

Number of n-node vertex-transitive graphs which are not Cayley graphs.

Orders of vertex-transitive graphs which are not Cayley graphs.

Primorial -1 primes: primes p such that -1 + product of primes up to p is prime.

A subclass of 2n-node trivalent planar graphs without triangles.

A subclass of 2n-node trivalent planar graphs without triangles.

A subclass of 2n-node trivalent planar graphs without triangles.

A subclass of 2n-node trivalent planar graphs without triangles.

Number of vertex-transitive graphs with n nodes.

Number of connected vertex-transitive graphs with n nodes.

Number of 2-dimensional directed compact animals of size n.

Log of e.g.f. for trees A000055(n-1).

Percolation series for hexagonal lattice.

Bond percolation series for directed cubic lattice.

Percolation series for b.c.c. lattice.

Percolation series for f.c.c. lattice.

Percolation series for directed hexagonal lattice.

Essentially a duplicate of A006727.

Bond percolation series for hexagonal lattice.