OFFSET
0,2
REFERENCES
B. N. Cyvin et al., Isomer enumeration of unbranched catacondensed polygonal systems with pentagons and heptagons, Match, No. 34 (Oct 1996), pp. 109-121.
MATHEMATICA
Table[Binomial[i, j]9^(i-j) 4^j, {i, 0, 10}, {j, 0, i}]//Flatten (* Harvey P. Dale, Sep 04 2019 *)
CROSSREFS
KEYWORD
AUTHOR
STATUS
approved