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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A325458 Triangle read by rows where T(n,k) is the number of integer partitions of n with largest hook of size k, i.e., with (largest part) + (number of parts) - 1 = k.

Original entry on oeis.org

1, 0, 1, 0, 0, 2, 0, 0, 0, 3, 0, 0, 0, 1, 4, 0, 0, 0, 0, 2, 5, 0, 0, 0, 0, 2, 3, 6, 0, 0, 0, 0, 0, 4, 4, 7, 0, 0, 0, 0, 0, 3, 6, 5, 8, 0, 0, 0, 0, 0, 1, 6, 8, 6, 9, 0, 0, 0, 0, 0, 0, 6, 9, 10, 7, 10, 0, 0, 0, 0, 0, 0, 2, 11, 12, 12, 8, 11
Offset: 0

Views

Author

Gus Wiseman, May 04 2019

Keywords

Comments

Conjectured to be equal to A049597.

Examples

			Triangle begins:
  1
  0  1
  0  0  2
  0  0  0  3
  0  0  0  1  4
  0  0  0  0  2  5
  0  0  0  0  2  3  6
  0  0  0  0  0  4  4  7
  0  0  0  0  0  3  6  5  8
  0  0  0  0  0  1  6  8  6  9
  0  0  0  0  0  0  6  9 10  7 10
  0  0  0  0  0  0  2 11 12 12  8 11
  0  0  0  0  0  0  2  9 16 15 14  9 12
  0  0  0  0  0  0  0  7 16 21 18 16 10 13
  0  0  0  0  0  0  0  4 18 23 26 21 18 11 14
  0  0  0  0  0  0  0  3 12 29 30 31 24 20 12 15
  0  0  0  0  0  0  0  1 12 27 40 37 36 27 22 13 16
  0  0  0  0  0  0  0  0  8 26 42 51 44 41 30 24 14 17
  0  0  0  0  0  0  0  0  6 23 48 57 62 51 46 33 26 15 18
  0  0  0  0  0  0  0  0  2 21 44 70 72 73 58 51 36 28 16 19
Row n = 9 counts the following partitions:
  (333)  (54)     (63)      (72)       (9)
         (432)    (522)     (621)      (81)
         (441)    (531)     (5211)     (711)
         (3222)   (4221)    (42111)    (6111)
         (3321)   (4311)    (321111)   (51111)
         (22221)  (32211)   (2211111)  (411111)
                  (33111)              (3111111)
                  (222111)             (21111111)
                                       (111111111)
		

Crossrefs

Row sums are A000041.
Column sums are 2^(k - 1) for k > 0.

Programs

  • Mathematica
    Table[Length[Select[IntegerPartitions[n],If[n==0,k==0,First[#]+Length[#]-1==k]&]],{n,0,19},{k,0,n}]

Formula

Franklin T. Adams-Watters has conjectured at A049597 that the k-th column gives the coefficients of the sum of Gaussian polynomials [k,m] for m = 0..k.