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A255768
Triangle read by rows: T(n,k) = total number of parts in all partitions of n into k distinct parts.
3
1, 3, 4, 2, 7, 5, 6, 14, 12, 20, 3, 8, 39, 7, 15, 52, 19, 13, 74, 41, 18, 102, 68, 4, 12, 134, 120, 9, 28, 158, 189, 24, 14, 208, 283, 51, 24, 259, 390, 107, 24, 284, 582, 173, 5, 31, 361, 749, 311, 11, 18, 409, 1024, 485, 29, 39, 488, 1289, 767, 61
OFFSET
1,2
COMMENTS
Column 1 is sigma = A000203.
Column 2 is A216669.
Row sums give A006128.
Row n has length A003056(n) hence the first element of column k is in row A000217(n).
The first positive element in column k is k.
LINKS
FORMULA
T(n,1) = A000203(n).
EXAMPLE
Triangle begins:
1;
3;
4, 2;
7, 5;
6, 14;
12, 20, 3;
8, 39, 7;
15, 52, 19;
13, 74, 41;
18, 102, 68, 4;
12, 134, 120, 9;
28, 158, 189, 24;
14, 208, 283, 51;
24, 259, 390, 107;
24, 284, 582, 173, 5;
31, 361, 749, 311, 11;
18, 409, 1024, 485, 29;
39, 488, 1289, 767, 61;
20, 538, 1699, 1114, 127;
42, 634, 2092, 1624, 238;
32, 678, 2642, 2291, 403, 6;
...
KEYWORD
nonn,tabf,look
AUTHOR
Omar E. Pol, May 21 2015
EXTENSIONS
a(27) and beyond from Alois P. Heinz, Jul 26 2015
STATUS
approved