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%I #10 Dec 29 2023 10:34:50
%S 1,0,1,0,2,1,0,2,4,1,0,4,8,6,1,0,2,16,18,8,1,0,12,24,44,32,10,1,0,-12,
%T 48,90,96,50,12,1,0,72,48,180,240,180,72,14,1,0,-190,160,308,544,530,
%U 304,98,16,1,0,700,-40,600,1120,1372,1032,476,128
%N Riordan array (1,x/sqrt(2-sqrt(1+4x))).
%C Factorizes as (1,xc(-x))*(1,x(1+x)/(1-2x)) where c(x) is the g.f. of A000108.
%C Row sums are A141344.
%C Triangle T(n,k), 0<=k<=n, read by rows, given by [0, 2, -1, -1, -1, -1, -1, -1, -1, ...] DELTA [1, 0, 0, 0, 0, 0, 0, ...] where DELTA is the operator defined in A084938. - _Philippe Deléham_, Nov 15 2008
%e Triangle begins
%e 1,
%e 0, 1,
%e 0, 2, 1,
%e 0, 2, 4, 1,
%e 0, 4, 8, 6, 1,
%e 0, 2, 16, 18, 8, 1,
%e 0, 12, 24, 44, 32, 10, 1,
%e 0, -12, 48, 90, 96, 50, 12, 1
%K easy,sign,tabl
%O 0,5
%A _Paul Barry_, Jun 26 2008