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A210953
Triangle read by rows: T(n,k) = sum of all parts in the k-th column of the shell model of partitions considering only the n-th shell and with its parts aligned to the right margin.
5
1, 0, 3, 0, 0, 5, 0, 0, 2, 9, 0, 0, 0, 3, 12, 0, 0, 0, 2, 9, 20, 0, 0, 0, 0, 3, 11, 25, 0, 0, 0, 0, 2, 9, 22, 38, 0, 0, 0, 0, 0, 3, 14, 28, 49, 0, 0, 0, 0, 0, 2, 9, 26, 44, 69, 0, 0, 0, 0, 0, 0, 3, 14, 37, 55, 87, 0, 0, 0, 0, 0, 0, 2, 9, 29, 62, 83, 123
OFFSET
1,3
EXAMPLE
For n = 6 and k = 1..6 the 6th shell looks like this:
-------------------------
k: 1, 2, 3, 4, 5, 6
-------------------------
. 6
. 3 + 3
. 4 + 2
. 2 + 2 + 2
. 1
. 1
. 1
. 1
. 1
. 1
. 1
.
The sums of all parts in columns 1-6 are
. 0, 0, 0, 2, 9, 20, the same as the 6th row of triangle.
Triangle begins:
1;
0, 3;
0, 0, 5;
0, 0, 2, 9;
0, 0, 0, 3, 12;
0, 0, 0, 2, 9, 20;
0, 0, 0, 0, 3, 11, 25;
0, 0, 0, 0, 2, 9, 22, 38;
0, 0, 0, 0, 0, 3, 14, 28, 49;
0, 0, 0, 0, 0, 2, 9, 26, 44, 69;
0, 0, 0, 0, 0, 0, 3, 14, 37, 55, 87;
0, 0, 0, 0, 0, 0, 2, 9, 29, 62, 83, 123;
CROSSREFS
Row sums give A138879. Column sums converge to A014153. Right border gives A046746, n >= 1.
Sequence in context: A361357 A305151 A127775 * A254280 A092669 A255986
KEYWORD
nonn,tabl
AUTHOR
Omar E. Pol, Apr 22 2012
STATUS
approved