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Triangular array T given by T(n,k)= number of 01-words of length n having exactly k 1's, every runlength of 1's odd and initial letter 0.
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%I #6 Mar 30 2012 18:57:05

%S 1,1,1,1,2,0,1,3,1,1,1,4,3,2,0,1,5,6,4,2,1,1,6,10,8,6,2,0,1,7,15,15,

%T 13,6,3,1,1,8,21,26,25,16,9,2,0,1,9,28,42,45,36,22,9,4,1,1,10,36,64,

%U 77,72,50,28,12,2,0,1,11,45,93,126,133,106,70,34,13,5,1,1,12,55,130,198,232

%N Triangular array T given by T(n,k)= number of 01-words of length n having exactly k 1's, every runlength of 1's odd and initial letter 0.

%C Row sums: A028495.

%D Clark Kimberling, Binary words with restricted repetitions and associated compositions of integers, in Applications of Fibonacci Numbers, vol.10, Proceedings of the Eleventh International Conference on Fibonacci Numbers and Their Applications, William Webb, editor, Congressus Numerantium, Winnipeg, Manitoba 194 (2009) 141-151.

%F T(n, k)=T(n-2, k)+T(n-2, k-1)+T(n-2, k-2)+T(n-3, k-1)-T(n-4, k-2) for 0<=k<=n, n>=1. (All numbers T(i, j) not in the array are 0, by definition of T.)

%e T(5,2) counts the words 01010, 01001, 00101. Top of triangle T:

%e 1 = T(1,0)

%e 1 1 = T(2,0) T(2,1)

%e 1 2 0 = T(3,0) T(3,1) T(3,2)

%e 1 3 1 1

%e 1 4 3 2 0

%Y Cf. A078804, A078806.

%K nonn,tabl

%O 1,5

%A _Clark Kimberling_, Dec 07 2002