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Bisection of Lucas triangle A060922: odd-indexed members of column sequences of A060922 (not counting leading zeros).
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%I #12 Dec 15 2019 21:59:18

%S 3,7,6,18,38,9,47,158,120,12,123,566,753,280,15,322,1880,3612,2568,

%T 545,18,843,5964,15040,16220,7043,942,21,2207,18342,57366,83780,57560,

%U 16536,1498,24,5778,55162,206115

%N Bisection of Lucas triangle A060922: odd-indexed members of column sequences of A060922 (not counting leading zeros).

%C Row sums give A060927. Column sequences (without leading zeros) are, for m=0..5: A005248(n+1), 2*A061171, A061172, 4*A061173, A061174, 2*A061175.

%C Companion triangle A060923 (even part).

%F a(n, m) = A060922(2*n+1-m, m).

%F a(n, m) = ((2*n-m+1)*A060923(n, m-1) + 2*(2*(2*n+1)-3*m)*a(n-1, m-1) + 4*(2*n-m)*A060923(n-1, m-1))/(5*m), m >= n >= 1; a(n, 0) = A005248(n); otherwise 0.

%F G.f. for column m >= 0: x^m*pLo(m+1, x)/(1-3*x+x^2)^(m+1), where pLo(n, x) := Sum_{m=0..n+floor((n-1)/2)} A061187(n-1, m)*x^m are the row polynomials of the (signed) staircase A061187.

%F T(n,k) = 3*T(n-1,k) + 2*T(n-1,k-1) - T(n-2,k) + 2*T(n-2,k-1) - T(n-2,k-2) + 4*T(n-3,k-2), T(0,0) = 3, T(1,0) = 7, T(1,1) = 6, T(2,0) = 18, T(2,1) = 38, T(2,2) = 9, T(n,k) = 0 if k < 0 or if k > n. - _Philippe Deléham_, Jan 21 2014

%e {3}; {7,6}; {18,38,9}; {47,158,120,12}; ...; pLo(2,x)= 2*(3+x-2*x^2).

%Y Cf. A005248.

%K nonn,easy,tabl

%O 0,1

%A _Wolfdieter Lang_, Apr 20 2001