A173383 Partial sums of A000014.

0, 1, 2, 2, 3, 4, 6, 8, 12, 17, 27, 41, 67, 109, 187, 319, 568, 1013, 1855, 3416, 6404, 12075, 23056, 44265, 85737, 166918, 327094, 643843, 1273776, 2529846, 5045015, 10094831, 20267469, 40811048, 82413473, 166854359, 338648851, 688887026, 1404384063, 2868791176, 5871429462, 12038444069

Offset

0,3

Comments

Number of series-reduced trees with <= n nodes.

Links

Table of n, a(n) for n=0..41.

Formula

a(n) = Sum_{k=0..n} A000014(k).

Crossrefs

Cf. A000014, A000055 (trees), A001678 (series-reduced planted trees), A007827 (series-reduced trees by leaves).

Sequence in context: A332755 A017912 A102543 * A316076 A368746 A325832

Adjacent sequences: A173380 A173381 A173382 * A173384 A173385 A173386

Keyword

easy,nonn

Author

Jonathan Vos Post, Feb 17 2010

Extensions

a(3)=2 inserted and edited by Georg Fischer, Sep 14 2021

Status

approved