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A214281 Triangle by rows, row n contains the ConvOffs transform of the first n terms of 1, 1, 3, 2, 5, 3, 7, ... (A026741 without leading zero). 3

%I #14 Feb 08 2022 22:16:07

%S 1,1,1,1,1,1,1,3,3,1,1,2,6,2,1,1,5,10,10,5,1,1,3,15,10,15,3,1,1,7,21,

%T 35,35,21,7,1,1,4,28,28,70,28,28,4,1,1,9,36,84,126,126,84,36,9,1,1,5,

%U 45,60,210,126,210,60,45,5,1,1,11,55,165,330,462,462,330,165,55,11,1

%N Triangle by rows, row n contains the ConvOffs transform of the first n terms of 1, 1, 3, 2, 5, 3, 7, ... (A026741 without leading zero).

%C The ConvOffs transform of a sequence s(0), s(1), ..., s(t-1) is defined by a(0)=1 and a(n) = a(n-1)*s(t-n)/s(n-1) for 1 <= n < t. An example of this process is also shown in the Narayana triangle, A001263. By increasing the length t of the input sequence (here: A026741) we create more and more rows of the triangle.

%H Tom Edgar and Michael Z. Spivey, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL19/Edgar/edgar3.html">Multiplicative functions, generalized binomial coefficients, and generalized Catalan numbers</a>, Journal of Integer Sequences, Vol. 19 (2016), Article 16.1.6.

%F T(n,k) = binomial(n,k) if n is odd.

%e First few rows of the triangle:

%e 1;

%e 1, 1;

%e 1, 1, 1;

%e 1, 3, 3, 1;

%e 1, 2, 6, 2, 1;

%e 1, 5, 10, 10, 5, 1;

%e 1, 3, 15, 10, 15, 3, 1;

%e 1, 7, 21, 35, 35, 21, 7, 1;

%e 1, 4, 28, 28, 70, 28, 28, 4, 1;

%e 1, 9, 36, 84, 126, 126, 84, 36, 9, 1;

%e 1, 5, 45, 60, 210, 126, 210, 60, 45, 5, 1;

%e 1, 11, 55, 165, 330, 462, 462, 330, 165, 55, 11, 1;

%e ...

%Y Cf. A134683 (row sums), A026741, A001263.

%K nonn,tabl,easy

%O 0,8

%A _Gary W. Adamson_, Jul 09 2012

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Last modified April 24 22:17 EDT 2024. Contains 371964 sequences. (Running on oeis4.)