OFFSET
0,2
COMMENTS
See a comment on V-V and V-S at A249246.
The overlap rules for the expansion are: (i) overlap within generation is allowed. (ii) overlap of different generations is prohibited.
There are a total of 16 combinations as shown in the table below:
+-------------------------------------------------------+
| Even n-th version V-V S-V V-S S-S |
+-------------------------------------------------------+
| Odd n-th version |
+-------------------------------------------------------+
Note: V-V = vertex to vertex, S-V = side to vertex,
V-S = vertex to side, S-S = side to side.
LINKS
Kival Ngaokrajang, Illustration of initial terms
FORMULA
Conjectures from Colin Barker, Sep 10 2015: (Start)
a(n) = a(n-2)+a(n-4)-a(n-6) for n>6.
G.f.: (7*x^6+3*x^5+20*x^4+9*x^3+8*x^2+3*x+1) / ((x-1)^2*(x+1)^2*(x^2+1)).
(End)
PROG
(PARI) {e=9; o=3; print1("1, ", o, ", ", e, ", "); for(n=3, 100, if (Mod(n, 2)==0, if (Mod(n, 4)==0, e=e+21); if (Mod(n, 4)==2, e=e+15); print1(e, ", "), if (Mod(n, 4)==3, o=o+9); if (Mod(n, 4)==1, o=o+6); print1(o, ", ")))}
CROSSREFS
KEYWORD
nonn
AUTHOR
Kival Ngaokrajang, Sep 06 2015
EXTENSIONS
Typo in data fixed by Colin Barker, Sep 10 2015
STATUS
approved