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[n, k]7^(n-k) 4^k, {n, 0, 10}, {k, 0, n}]//Flatten (* Harvey P. Dale, May 26 2020 *)
CROSSREFS
KEYWORD
AUTHOR
STATUS
approved