1, 1, 2, 1, 3, 6, 1, 4, 10, 20, 1, 5, 15, 35, 70, 1, 6, 21, 56, 126, 252, 1, 7, 28, 84, 210, 462, 924, 1, 8, 36, 120, 330, 792, 1716, 3432, 1, 9, 45, 165, 495, 1287, 3003, 6435, 12870, 1, 10, 55, 220, 715, 2002, 5005, 11440, 24310, 48620, 1, 11, 66, 286, 1001
Offset: 0
The triangle is the lower triangular part of the square array:
1| 1, 1, 1, 1, 1, 1, 1, 1, 1, ...
1, 2| 3, 4, 5, 6, 7, 8, 9, 10, ...
1, 3, 6| 10, 15, 21, 28, 36, 45, 55, ...
1, 4, 10, 20| 35, 56, 84, 120, 165, 220, ...
1, 5, 15, 35, 70| 126, 210, 330, 495, 715, ...
1, 6, 21, 56, 126, 252| 462, 792, 1287, 2002, ...
1, 7, 28, 84, 210, 462, 924| 1716, 3003, 5005, ...
1, 8, 36, 120, 330, 792, 1716, 3432| 6435, 11440, ...
1, 9, 45, 165, 495, 1287, 3003, 6435, 12870| 24310, ...
1, 10, 55, 220, 715, 2002, 5005, 11440, 24310, 48620| ...
The array read by antidiagonals gives the binomial triangle.
From _Reinhard Zumkeller_, Jul 27 2012: (Start)
Take the first n elements of the n-th diagonal (NW to SE) of left half of Pascal's triangle and write it as n-th row on the triangle on the right side, see above
0: 1 1
1: 1 _ 1 2
2: 1 2 __ 1 3 6
3: 1 3 __ __ 1 4 10 20
4: 1 4 6 __ __ 1 5 15 35 70
5: 1 5 10 __ __ __ 1 6 21 56 .. ..
6: 1 6 15 20 __ __ __ 1 7 28 .. .. .. ..
7: 1 7 21 35 __ __ __ __ 1 8 .. .. .. .. .. ..
8: 1 8 28 56 70 __ __ __ __ 1 .. .. .. .. .. .. .. .. (End)
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