%I A038763
%S A038763 1,1,1,1,4,3,1,7,15,9,1,10,36,54,27,1,13,66,162,189,81,1,16,105,360,
%T A038763 675,648,243,1,19,153,675,1755,2673,2187,729,1,22,210,1134,3780,7938,
%U A038763 10206,7290,2187,1,25,276,1764,7182,19278,34020,37908,24057,6561,1,28
%N A038763 Triangular matrix arising in enumeration of catafusenes, read by rows.
%C A038763 Triangle T(n,k), 0<=k<=n, read by rows, given by [1, 0, 0, 0, 0, 0, 0, 
               0, 0, 0, ...] DELTA [1, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, ...] where 
               DELTA is the operator defined in A084938 . - DELEHAM Philippe (kolotoko(aT)lagoon.nc), 
               Aug 10 2005
%C A038763 Mirror image of A136158 . - Philippe DELEHAM (kolotoko(AT)wanadoo.fr), 
               Dec 17 2007
%C A038763 Triangle read by rows, n-th row = X^(n-1) * [1, 1, 0, 0, 0,...] where 
               X = an infinite bidiagonal matrix with (1,1,1,...) in the main diagonal 
               and (3,3,3,..) in the subdiagonal; given row 0 = 1. - Gary W. Adamson 
               (qntmpkt(AT)yahoo.com), Jul 19 2008
%D A038763 S. J. Cyvin et al., Unbranched catacondensed polygonal systems containing 
               hexagons and tetragons, Croatica Chem. Acta, 69 (1996), 757-774.
%F A038763 a(n, 0)=1; a(1, 1)=1; a(n, k)=0 for k>n; a(n, k)=a(n-1, k-1)*3+a(n-1, 
               k) for n >= 2.
%F A038763 Sum_[k, 0<=k<=n} T(n,k)= A081294(n) . - Philippe DELEHAM (kolotoko(AT)wanadoo.fr), 
               Sep 22 2006
%F A038763 T(n,k)=A136158(n,n-k). - Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Dec 
               17 2007
%e A038763 1; 1,1; 1,4,3; 1,7,15,9; ...
%Y A038763 Cf. A024462.
%Y A038763 Sequence in context: A103552 A127673 A016698 this_sequence A128007 A098458 
               A165914
%Y A038763 Adjacent sequences: A038760 A038761 A038762 this_sequence A038764 A038765 
               A038766
%K A038763 tabl,nonn,easy
%O A038763 0,5
%A A038763 N. J. A. Sloane (njas(AT)research.att.com), May 03 2000
%E A038763 More terms from James A. Sellers (sellersj(AT)math.psu.edu), May 03 2000