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A245100
Triangle read by rows in which row n lists the parts of the symmetric representation of sigma(n), multiplied by n.
1
1, 6, 6, 6, 28, 15, 15, 72, 28, 28, 120, 45, 27, 45, 90, 90, 66, 66, 336, 91, 91, 168, 168, 120, 120, 120, 496, 153, 153, 702, 190, 190, 840, 231, 105, 105, 231, 396, 396, 276, 276, 1440, 325, 125, 325, 546, 546, 378, 162, 162, 378, 1568, 435, 435, 2160, 496, 496, 2016
OFFSET
1,2
COMMENTS
Row sums give A064987.
Since both A000203(n) and A024916(n) have a symmetric representation then both row n and the triangle have can be represented as a symmetric polycube.
FORMULA
T(n,k) = n*A237270(n,k).
EXAMPLE
The irregular triangle begins:
1;
6;
6, 6;
28;
15, 15;
72;
28, 28;
120;
45, 27, 45;
90, 90;
66, 66;
336;
91, 91;
168, 168;
120, 120, 120;
496;
153, 153;
702;
190, 190;
840;
231, 105, 105, 231;
...
For n = 9 the parts of the symmetric representation of sigma(9) are [5, 3, 5], so row 9 is [45, 27, 45].
KEYWORD
nonn,tabf
AUTHOR
Omar E. Pol, Jul 11 2014
STATUS
approved