OFFSET
1,5
COMMENTS
This is a variation of A335780 where only the nodes have mass. See that sequence for further details of the allowed walks.
EXAMPLE
a(1)-a(4) = 1 as the only stable walk is a walk straight down from the first node.
a(5) = 5. There are two stable walks with a first step to the right:
.
X-----+
| + X-----+
| | |
+-----+-----+ | |
| +-----+-----+
|
+
.
Assuming a node mass of p, both walks have a torque of 2p to the right and 2p to the left of the first node. These walks can be taken in 2 ways. Thus, with the straight down walk, the total number of stable walks is 2*2+1 = 5.
CROSSREFS
KEYWORD
nonn,walk,more
AUTHOR
Scott R. Shannon, Sep 12 2020
STATUS
approved