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Triangle whose (i,j)-th entry is binomial(i,j)*12^(i-j)*9^j.
1

%I #9 Nov 22 2022 11:29:48

%S 1,12,9,144,216,81,1728,3888,2916,729,20736,62208,69984,34992,6561,

%T 248832,933120,1399680,1049760,393660,59049,2985984,13436928,25194240,

%U 25194240,14171760,4251528,531441,35831808,188116992,423263232

%N Triangle whose (i,j)-th entry is binomial(i,j)*12^(i-j)*9^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.

%e 1

%e 12 9

%e 144 216 81

%e 1728 3888 2916 729

%e 20736 62208 69984 34992 6561

%e 248832 933120 1399680 1049760 393660 59049

%e 2985984 13436928 25194240 25194240 14171760 4251528 531441

%p A038335 := proc(i,j)

%p binomial(i,j)*12^(i-j)*9^j ;

%p end proc: # _R. J. Mathar_, Nov 22 2022

%t Flatten[Table[Binomial[i,j]12^(i-j) 9^j,{i,0,10},{j,0,i}]] (* _Harvey P. Dale_, Oct 17 2013 *)

%Y Cf. A009965 (row sums), A001021 (column 0), A001019 (diagonal)

%K nonn,tabl,easy

%O 0,2

%A _N. J. A. Sloane_.