A339039 - OEIS

A339039

Number of unlabeled connected simple graphs with n edges rooted at one distinguished vertex.

1, 1, 2, 5, 13, 37, 114, 367, 1248, 4446, 16526, 63914, 256642, 1067388, 4590201, 20376849, 93240065, 439190047, 2126970482, 10579017047, 53983000003, 282345671127, 1512273916781, 8287870474339, 46438619162441, 265840311066579

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,3

LINKS

Table of n, a(n) for n=0..25.

FORMULA

G.f.: f(x)/g(x) where f(x) is the g.f. of A053419 and g(x) is the g.f. of A000664.

PROG

(PARI) \\ See A339063 for G.

seq(n)={my(A=O(x*x^n)); Vec(G(2*n, x+A, [1])/G(2*n, x+A, []))}

CROSSREFS

Cf. A000664, A002905, A053419, A126100, A303832, A339036, A339040, A339041, A339044, A339063.

Sequence in context: A170941 A119495 A148301 * A205544 A149855 A149856

Adjacent sequences: A339036 A339037 A339038 * A339040 A339041 A339042

KEYWORD

nonn

AUTHOR

Andrew Howroyd, Nov 20 2020

STATUS

approved