%I #7 Mar 30 2012 17:38:34
%S 1,9,9,81,162,81,729,2187,2187,729,6561,26244,39366,26244,6561,59049,
%T 295245,590490,590490,295245,59049,531441,3188646,7971615,10628820,
%U 7971615,3188646,531441,4782969,33480783,100442349,167403915
%N Triangle whose (i,j)-th entry is binomial(i,j)*9^(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.
%F Row sums: sum_{j=0..i} T(i,j) = A001027(i). [From _R. J. Mathar_, Mar 30 2009]
%K nonn,tabl,easy
%O 0,2
%A _N. J. A. Sloane_.
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