A176724 Triangle for number of partitions which define multiset repetition classes.
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
Examples
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; ...
Links
- W. Lang: First 15 rows and row sums.
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}.
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.
Extensions
Edited (in response to comments by Franklin T. Adams-Watters) by Wolfdieter Lang, Apr 02 2011
Comments