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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.

A337586 Triangle read by rows: T(n, k) is the number of integer multisets of size k (partitions of k) for which the number of partitions of n with matching multiplicity multiset is odd (n >= 1, 1 <= k <= n).

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 0, 0, 1, 1, 1, 1, 3, 2, 1, 1, 1, 1, 2, 1, 2, 1, 1, 1, 2, 1, 3, 3, 2, 1, 1, 1, 0, 3, 0, 3, 3, 2, 1, 1, 1, 1, 0, 3, 3, 3, 3, 2, 1, 1, 1, 1, 2, 3, 2, 1, 5, 3, 2, 1, 1, 1, 2, 2, 1, 3, 7, 3, 5, 3, 2, 1, 1, 1, 0, 0, 2, 2, 2, 5, 3, 5, 3, 2, 1, 1, 1, 1, 0, 3, 3, 4, 5, 5, 3, 5, 3
Offset: 1

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Author

Álvar Ibeas, Sep 02 2020

Keywords

Comments

The relevant partitions of n have exactly k parts.
The number of multiplicity multisets of size k met by a positive even number of partitions of n is A337584(n, k) - T(n, k).

Examples

			The 3 = A008284(6, 2) partitions of 6 into 2 parts show 2 = A337584(6, 2) different multiplicity multisets: (1, 1) is attained by two of those partitions ((5, 1) and (4, 2)) and the other (2) just by one, (3, 3). Then, T(6, 2) = 1.
Triangle begins:
  k:  1 2 3 4 5 6 7 8 9 10
      --------------------
n=1:  1
n=2:  1 1
n=3:  1 1 1
n=4:  1 2 1 1
n=5:  1 0 0 1 1
n=6:  1 1 3 2 1 1
n=7:  1 1 2 1 2 1 1
n=8:  1 2 1 3 3 2 1 1
n=9:  1 0 3 0 3 3 2 1 1
n=10: 1 1 0 3 3 3 3 2 1 1
		

Crossrefs

Cf. A008284, A337585 (row sums), A337584.

Formula

T(n, k) == A008284(n, k) (mod 2).
If k > (2*n+1)/3, T(n, k) = A337585(n - k).