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Triangle whose (i,j)-th entry is binomial(i,j)*9^(i-j)*4^j.
0

%I #7 Sep 04 2019 18:30:39

%S 1,9,4,81,72,16,729,972,432,64,6561,11664,7776,2304,256,59049,131220,

%T 116640,51840,11520,1024,531441,1417176,1574640,933120,311040,55296,

%U 4096,4782969,14880348,19840464,14696640,6531840,1741824,258048

%N Triangle whose (i,j)-th entry is binomial(i,j)*9^(i-j)*4^j.

%D B. N. Cyvin et al., Isomer enumeration of unbranched catacondensed polygonal systems with pentagons and heptagons, Match, No. 34 (Oct 1996), pp. 109-121.

%t Table[Binomial[i,j]9^(i-j) 4^j,{i,0,10},{j,0,i}]//Flatten (* _Harvey P. Dale_, Sep 04 2019 *)

%K nonn,tabl,easy

%O 0,2

%A _N. J. A. Sloane_.