A173422 Partials sums of A003094 (unlabeled connected planar simple graphs with n nodes).

1, 2, 3, 5, 11, 31, 130, 776, 6750, 78635, 1131440, 18580739, 331953037

Offset: 0

Author

Jonathan Vos Post, Feb 18 2010

Keywords

• hard
• nonn

Comments

Partials sums of number of unlabeled connected planar simple graphs with n nodes. The subsequence of primes in these partial sums begins: 2, 3, 5, 11, 31.

Examples

			a(11) = 1 + 1 + 1 + 2 + 6 + 20 + 99 + 646 + 5974 + 71885 + 1052805 + 17449299.
		

Crossrefs

Cf. A003094, inverse Euler transform of A005470, A126201.

Programs

PARI

S=0; A173422=apply(t->S+=t,A003094) \\ with A003094 defined as vector of the initial terms of that sequence. - M. F. Hasler, Mar 20 2018

Formula

a(n) = Sum_{i=0..n} A003094(i).

Extensions

Edited and a(12) added by M. F. Hasler, Mar 20 2018