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A Catalan triangle read by rows, derived from the INVERT transform of initial segments of the Catalan numbers A000108.
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%I #11 Aug 07 2012 13:17:46

%S 1,1,1,1,2,2,1,4,4,5,1,7,10,10,14,1,12,24,25,28,42,1,20,52,70,70,84,

%T 132,1,33,112,185,196,210,264,429,1,54,238,445,588,588,660,858,1430,1,

%U 88,496,1080,1652,1764,1848,2145,2860,4862,1,143,1026,2610,4242,5544,5544,6006,7150,9724,16796

%N A Catalan triangle read by rows, derived from the INVERT transform of initial segments of the Catalan numbers A000108.

%C Create an array in which the n-th row (n >= 1) is the INVERT transform of the first n terms of A000108: (1, 1, 2, 5, 14,...) followed by zeros. For example, row 3 of the array is the INVERT transform of (1, 1, 2, 0, 0, 0,...). The array is:

%C 1,...1,...1,...1,...1,...1,...

%C 1,...2,...3,...5,...8,..13,...

%C 1,...2,...5,...9,..18,..37,...

%C 1,...2,...5,..14,..28,..62,...

%C ...

%C Then the rows of the triangle are first differences of the COLUMNS of this array.

%C Row sums = the Catalan sequence A000108 starting with offset 1. Right border = the Catalan sequence.

%e First few rows of the triangle are:

%e 1;

%e 1, 1;

%e 1, 2, 2;

%e 1, 4, 4, 5;

%e 1, 7, 10, 10, 14;

%e 1, 12, 24, 25, 28, 42;

%e 1, 20, 52, 70, 70, 84, 132;

%e 1, 33, 112, 185, 196, 210, 264, 429;

%e 1, 54, 238, 445, 588, 588, 660, 858, 1430;

%e ...

%Y Cf. A000108.

%K nonn,tabl

%O 1,5

%A _Gary W. Adamson_, Jun 25 2012

%E Edited by _N. J. A. Sloane_, Jul 03 2012