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Revision History for A364536 (Underlined text is an addition; strikethrough text is a deletion.)

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A364536 Number of strict integer partitions of n where some part is a difference of two consecutive parts.
(history; published version)
#9 by Andrew Howroyd at Tue Sep 26 13:39:09 EDT 2023
STATUS

reviewed

approved

#8 by Michel Marcus at Tue Sep 26 12:54:34 EDT 2023
STATUS

proposed

reviewed

#7 by Chai Wah Wu at Tue Sep 26 12:53:43 EDT 2023
STATUS

editing

proposed

#6 by Chai Wah Wu at Tue Sep 26 12:53:38 EDT 2023
PROG

(Python)

from collections import Counter

from sympy.utilities.iterables import partitions

def A364536(n): return sum(1 for s, p in map(lambda x: (x[0], tuple(sorted(Counter(x[1]).elements()))), filter(lambda p:max(p[1].values(), default=1)==1, partitions(n, size=True))) if not set(p).isdisjoint({p[i+1]-p[i] for i in range(s-1)})) # Chai Wah Wu, Sep 26 2023

STATUS

approved

editing

#5 by Michael De Vlieger at Mon Jul 31 21:47:53 EDT 2023
STATUS

proposed

approved

#4 by Gus Wiseman at Mon Jul 31 19:56:18 EDT 2023
STATUS

editing

proposed

#3 by Gus Wiseman at Mon Jul 31 19:56:02 EDT 2023
NAME

Number of strict integer partitions of n where some part withis partsa notdifference disjointof fromtwo firstconsecutive differencesparts.

COMMENTS

In other words, somestrict partpartitions iswith aparts differencenot ofdisjoint twofrom consecutivefirst partsdifferences.

CROSSREFS

For all differences of pairs parts we have A363226 (complement A364346), , non-strict A363225 (complement A364345)..

For all non-differences of pairs we have A364346, strict A364345.

For subsets of {1..n} instead of partitions we have A364466, complement A364463.

The non-strict case is A364467, complementranks A363260A364537.

A323092 counts double-free partitions, ranks A320340, subsets A050291 (complementstrict A088808).A120641.

A325325 counts partitions with distinct first-differences, strict A320347.

Cf. A002865, A025065, `, A093971, A108917, `A196723, A229816, A236912, A237113, A237667, A320347, A326083, A363225, A364347.

#2 by Gus Wiseman at Mon Jul 31 04:13:14 EDT 2023
NAME

allocatedNumber of strict integer partitions of n with parts not disjoint forfrom Gusfirst Wisemandifferences.

DATA

0, 0, 0, 1, 0, 0, 2, 1, 2, 2, 5, 4, 6, 6, 9, 11, 16, 17, 23, 25, 30, 38, 48, 55, 65, 78, 92, 106, 127, 146, 176, 205, 230, 277, 315, 366, 421, 483, 552, 640, 727, 829, 950, 1083, 1218, 1408, 1577, 1794, 2017, 2298, 2561, 2919, 3255, 3685, 4116, 4638, 5163

OFFSET

0,7

COMMENTS

In other words, some part is a difference of two consecutive parts.

EXAMPLE

The a(3) = 1 through a(15) = 11 partitions (A = 10, B = 11, C = 12):

21 . . 42 421 431 63 532 542 84 742 743 A5

321 521 621 541 632 642 841 752 843

631 821 651 A21 761 942

721 5321 921 5431 842 C21

4321 5421 6421 B21 6432

6321 7321 6431 6531

6521 7431

7421 7521

8321 8421

9321

54321

MATHEMATICA

Table[Length[Select[IntegerPartitions[n], UnsameQ@@#&&Intersection[#, -Differences[#]]!={}&]], {n, 0, 30}]

CROSSREFS

For all differences of pairs parts we have A363226 (complement A364346), non-strict A363225 (complement A364345).

The strict complement is counted by A364464, non-strict A363260.

For subsets of {1..n} instead of partitions we have A364466, complement A364463.

The non-strict case is A364467, complement A363260.

A000041 counts integer partitions, strict A000009.

A008284 counts partitions by length, strict A008289.

A323092 counts double-free partitions, ranks A320340, subsets A050291 (complement A088808).

A325325 counts partitions with distinct first-differences.

Cf. A002865, A025065, `A093971, A108917, `A196723, A229816, A236912, A237113, A237667, A320347, A326083, A363225, A364347.

KEYWORD

allocated

nonn

AUTHOR

Gus Wiseman, Jul 31 2023

STATUS

approved

editing

#1 by Gus Wiseman at Thu Jul 27 21:46:07 EDT 2023
NAME

allocated for Gus Wiseman

KEYWORD

allocated

STATUS

approved

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Last modified August 29 12:15 EDT 2024. Contains 375517 sequences. (Running on oeis4.)