OFFSET
1,17
COMMENTS
The array with all ranks (including negative ones) is A063995.
a(n,-r)=a(n,r) for negative rank -r with r from 1,2,...,n-1 (due to conjugation of partitions of n; see the link).
Dyson's rank of a partition of n is the maximal part minus the number of parts, i.e. the number of columns minus the number of rows of the Ferrers diagram (see the link) of the partition.
LINKS
Lars Blomberg, Table of n, a(n) for n = 1..5050
Wolfdieter Lang, First 16 rows.
Alexander Berkovich and Frank G. Garvan, Some observations on Dyson's new symmetries of partitions, Journal of Combinatorial Theory, Series A 100.1 (2002): 61-93.
Freeman J. Dyson, Problems for solution nr. 4261, Am. Math. Month. 54 (1947) 418.
Freeman J. Dyson, A new symmetry of partitions, Journal of Combinatorial Theory 7.1 (1969): 56-61. See Table 1.
Freeman J. Dyson, Mappings and symmetries of partitions, J. Combin. Theory Ser. A 51 (1989), 169-180.
Eric Weisstein's World of Mathematics, Conjugation of partitions of n.
Eric Weisstein's World of Mathematics, Ferrers diagram.
FORMULA
a(n, r)= number of partitions of n with rank r, with r from 0, 1, ..., n-1.
G.f. of column r: (1/Product_{k>=1} (1-x^k)) * Sum_{k>=1} (-1)^(k-1) * x^(r*k) * ( x^(k*(3*k-1)/2) - x^(k*(3*k+1)/2) ). - Seiichi Manyama, May 21 2023
EXAMPLE
Triangle starts:
1;
0, 1;
1, 0, 1;
1, 1, 0, 1;
1, 1, 1, 0, 1;
1, 2, 1, 1, 0, 1; ...
Row 6, second entry is 2 because there are 2 partitions of n=6 with rank r=2-1=1, namely (3^2) and (1^2,4).
The table of p(n,m) = number of partitions of n with rank m, taken from Dyson (1969):
n\m -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6
-----------------------------------------------------
0 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
1 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0,
2 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0,
3 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0,
4 0, 0, 0, 1, 0, 1, 1, 1, 0, 1, 0, 0, 0,
5 0, 0, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 0,
6 0, 1, 0, 1, 1, 2, 1, 2, 1, 1, 0, 1, 0,
7 1, 0, 1, 1, 2, 1, 3, 1, 2, 1, 1, 0, 1,
...
The central triangle is A063995, the right-hand triangle is the present sequence. - N. J. A. Sloane, Jan 23 2020
CROSSREFS
KEYWORD
AUTHOR
Wolfdieter Lang, Mar 11 2005
STATUS
approved