OFFSET
0,2
COMMENTS
See A348227 for much more information about this structure.
LINKS
Rémy Sigrist, PARI program for A348231
FORMULA
G.f. = (1 + 8*q + 14*q^2 + 12*q^3 + q^4)/(1 - q^2)^2. [This has not yet been officially proved, but it will follow from the "coloring book" method in the same way that the g.f. for A348227 was established.]
PROG
(PARI) See Links section.
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Oct 08 2021
EXTENSIONS
More terms from Rémy Sigrist, Oct 09 2021
STATUS
approved