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A210971
Triangle read by rows in which row n lists the region number of the parts of the k-th partition of n, with partitions reverse lexicographically ordered.
3
1, 3, 2, 6, 5, 3, 11, 10, 8, 9, 5, 18, 17, 15, 16, 12, 13, 7, 29, 28, 26, 27, 23, 24, 18, 28, 20, 21, 11
OFFSET
1,2
COMMENTS
Each part of a partition of n belongs to a different region of n. The "region number" of a part of the r-th region of n is equal to r. For the definition of "region of n" see A206437.
EXAMPLE
For n = 5 we have:
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. Two arrangements Sum of
k of the partitions of 5 partition k
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7 [5] [5] 5
6 [3+2] [3+2] 5
5 [4+1] [4 +1] 5
4 [2+1+1] [2+2 +1] 5
3 [3+1+1] [3 +1 +1] 5
2 [2+1+1+1] [2+1 +1 +1] 5
1 [1+1+1+1+1] [1+1+1 +1 +1] 5
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. Two arrangements
. of the region numbers Sum of
k of the partitions of 5 zone k
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7 [7] [7] 7
6 [6,7] [6,7] 13
5 [5,7] [5, 7] 12
4 [4,5,7] [4,5, 7] 16
3 [3,5,7] [3, 5, 7] 15
2 [2,3,5,7] [2,3, 5, 7] 17
1 [1,2,3,5,7] [1,2,3, 5, 7] 18
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So row 5 of triangle gives: 18, 17, 15, 16, 12, 13, 7.
.
Triangle begins:
1;
3,2;
6,5,3;
11,10,8,9,5;
18,17,15,16,12,13,7;
29,28,26,27,23,24,18,28,20,21,11;
CROSSREFS
Column 1 is A026905. Right border = row lengths = A000041, n>=1. Row sums give A210972.
Sequence in context: A234922 A049777 A193999 * A212000 A058401 A244426
KEYWORD
nonn,tabf,more
AUTHOR
Omar E. Pol, Jun 30 2012
STATUS
approved