cp's OEIS Frontend

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.

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A337585 a(n) is the number of integer multisets (partitions) for which the number of partitions of n with matching multiplicity multiset is odd.

Original entry on oeis.org

1, 1, 2, 3, 5, 3, 9, 9, 14, 14, 18, 22, 31, 27, 37, 42, 65, 61, 83, 82, 111, 110, 142, 147, 187, 190, 230, 242, 296, 319, 358, 412, 471, 505, 600, 595, 753, 781, 895, 921, 1082, 1143, 1272, 1405, 1587, 1632, 1872, 2000, 2263, 2419, 2648, 2799, 3223, 3319, 3723
Offset: 0

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Author

Álvar Ibeas, Sep 02 2020

Keywords

Comments

The number of multiplicity multisets met by a positive even number of partitions of n is A088887(n) - a(n).
The parity of a(n) is A040051(n).

Examples

			The partitions of 7 exhibit 10 = A088887(7) different multisets of multiplicities. Except for (3, 1) (met by partitions (4, 1, 1, 1) and (2, 2, 2, 1)), an odd number of partitions of 7 lead to each of them, so a(7) = 9.
		

Crossrefs

Cf. A088887.

Formula

a(n) = Sum_{k odd} A337583(n, k).

A337587 a(n) is the maximum size among sets of partitions of n with the same multiplicity multiset.

Original entry on oeis.org

1, 1, 1, 1, 1, 2, 2, 3, 3, 4, 4, 7, 8, 11, 11, 17, 17, 23, 23, 30, 36, 44, 56, 65, 79, 91, 110, 124, 146, 165, 189, 212, 245, 280, 343, 393, 465, 530, 623, 698, 815, 910, 1043, 1163, 1325, 1464, 1690, 1898, 2190, 2590, 2981, 3458, 3965, 4568, 5156, 5931, 6689, 7571
Offset: 0

Views

Author

Álvar Ibeas, Sep 02 2020

Keywords

Examples

			a(7) = 3, cardinality reached by two sets. On the one hand, the multiplicities of the three partitions (6, 1), (5, 2), and (4, 3) are (1, 1). On the other hand, those of (5, 1, 1), (3, 3, 1) and (3, 2, 2) are (2, 1).
		

Crossrefs

Cf. A337583.
Showing 1-2 of 2 results.