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A176724
Triangle for number of partitions which define multiset repetition classes.
4
1, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 0, 0, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 1, 2, 1, 1, 1, 0, 0, 0, 1, 0, 1, 2, 1, 1, 1, 0, 0, 0, 0, 1, 0, 1, 2, 1, 1, 1, 0, 0, 0, 0, 0, 2, 1, 2, 2, 1, 1, 1, 0, 0, 0, 0, 0, 1, 2, 1, 2, 2, 1, 1, 1, 0, 0, 0, 0, 0, 0, 1, 2, 1, 2, 2, 1, 1, 1
OFFSET
1,42
COMMENTS
For definitions, references, links and examples see the corresponding partition array A176723.
Row sums coincide with those of array A176723 for n>=1, and they are given by A007294.
If for n=0 a 1 is added (the empty partition defines the empty multiset class) the tabl structure will be lost.
FORMULA
a(n,m) is the number of m part partitions of n which define m-multiset repetition classes. Multiset repetition class defining is equivalent to the following constraint on the exponents of a partition (1^e[1],2^e[2],...,M^e[M]):
e[1] >= e[2]>=...>=e[M]>=1, i.e., positive nonincreasing with largest part M. This will satisfy T(M) <= n where T(M) = A000217(M) are the triangular numbers; for each n every sufficiently small positive M does occur.
EXAMPLE
1;
0,1;
0,1,1;
0,0,1,1;
0,0,0,1,1;
0,0,1,1,1,1;
0,0,0,1,1,1,1;
...
CROSSREFS
a(7,5)=1 because there is only one 5 part partition of 7 which is 5-multiset repetition class defining, namely (1^3,2^2) (see row n=7 of the partition array A176723). This defines the 5-multiset class representative {1,1,1,2,2}.
Sequence in context: A321929 A089198 A059607 * A015318 A026836 A089052
KEYWORD
nonn,easy,tabl
AUTHOR
Wolfdieter Lang, Jul 14 2010
EXTENSIONS
Edited (in response to comments by Franklin T. Adams-Watters) by Wolfdieter Lang, Apr 02 2011
STATUS
approved