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%I #10 Jan 26 2020 21:47:07
%S 1,0,2,0,1,5,0,0,4,12,0,0,1,14,29,0,0,0,6,44,70,0,0,0,1,27,131,169,0,
%T 0,0,0,8,104,376,408,0,0,0,0,1,44,366,1052,985,0,0,0,0,0,10,200,1212,
%U 2888,2378,0,0,0,0,0,1,65,810,3842,7813,5741,0,0,0,0,0,0,12,340,3032,11784
%N A skew Pell-Pascal triangle.
%C Main diagonal is A000129. Row sums are A002605. Column sums are A006190(n+1).
%C A skewed version of the Riordan array (1/(1-2x-x^2), x/(1-2x-x^2)), see A054456. - _Philippe Deléham_, Nov 21 2007
%C Triangle, read by rows, given by [0,1/2,-1/2,0,0,0,0,0,...] DELTA [2,1/2,-1/2,0,0,0,0,0,...] where DELTA is the operator defined in A084938. - _Philippe Deléham_, Jan 30 2010
%F G.f.: 1/(1-2xy(1+x/2)-x^2*y^2);
%F T(n, k) = Sum_{j=0..floor((2k-n)/2)} C(k-j, n-k)*C(2k-n, j)*2^(2k-2j-n)};
%F T(n, k) = 2*T(n-1, k-1) + T(n-2, k-1) + T(n-2, k-2).
%e Rows begin
%e 1;
%e 0, 2;
%e 0, 1, 5;
%e 0, 0, 4, 12;
%e 0, 0, 1, 14, 29;
%e 0, 0, 0, 6, 44, 70;
%e 0, 0, 0, 1, 27, 131, 169;
%e 0, 0, 0, 0, 8, 104, 376, 408;
%Y Cf. A111006, A112906. - _Philippe Deléham_, Jan 30 2010
%K easy,nonn,tabl
%O 0,3
%A _Paul Barry_, Oct 05 2005
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