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%I #10 Aug 09 2017 23:34:25
%S 1,12,1,144,24,1,1728,432,36,1,20736,6912,864,48,1,248832,103680,
%T 17280,1440,60,1,2985984,1492992,311040,34560,2160,72,1,35831808,
%U 20901888,5225472,725760,60480,3024,84,1,429981696,286654464,83607552
%N Triangle whose (i,j)-th entry is binomial(i,j)*12^(i-j)*1^j.
%C T(i,j) is the number of i-permutations of 13 objects a,b,c,d,e,f,g,h,i,j,k,l,m, with repetition allowed, containing j a's. - _Zerinvary Lajos_, Dec 21 2007
%C These are the rows of A013619 read right to left. Row sums are A001022(i). - _R. J. Mathar_, Mar 05 2008
%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, 1
%e 144, 24, 1
%e 1728, 432, 36, 1
%e 20736, 6912, 864, 48, 1
%e 248832, 103680, 17280, 1440, 60, 1
%e 2985984, 1492992, 311040, 34560, 2160, 72, 1
%e 35831808, 20901888, 5225472, 725760, 60480, 3024, 84, 1
%p for i from 0 to 7 do seq(binomial(i, j)*12^(i-j), j = 0 .. i) od; # _Zerinvary Lajos_, Dec 21 2007
%K nonn,tabl,easy
%O 0,2
%A _N. J. A. Sloane_