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A325349 Number of integer partitions of n whose augmented differences are distinct. 16
1, 1, 1, 2, 3, 2, 4, 5, 7, 7, 12, 10, 13, 15, 21, 21, 31, 34, 38, 45, 55, 60, 71, 80, 84, 103, 119, 134, 152, 186, 192, 228, 263, 292, 321, 377, 399, 454, 514, 565, 618, 709, 752, 840, 958, 1050, 1140, 1297, 1402, 1568, 1755, 1901, 2080, 2343, 2524, 2758, 3074 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,4
COMMENTS
The augmented differences aug(y) of an integer partition y of length k are given by aug(y)_i = y_i - y_{i + 1} + 1 if i < k and aug(y)_k = y_k. For example, aug(6,5,5,3,3,3) = (2,1,3,1,1,3).
The Heinz numbers of these partitions are given by A325366.
LINKS
Fausto A. C. Cariboni, Table of n, a(n) for n = 0..440
EXAMPLE
The a(1) = 1 through a(11) = 10 partitions (A = 10, B = 11):
(1) (2) (3) (4) (5) (6) (7) (8) (9) (A) (B)
(21) (22) (41) (33) (43) (44) (54) (55) (65)
(31) (42) (52) (62) (63) (64) (83)
(51) (61) (71) (72) (73) (92)
(421) (422) (81) (82) (A1)
(431) (522) (91) (443)
(521) (621) (433) (641)
(442) (722)
(541) (731)
(622) (821)
(631)
(721)
For example, (4,4,3) has augmented differences (1,2,3), which are distinct, so (4,4,3) is counted under a(11).
MATHEMATICA
Table[Length[Select[IntegerPartitions[n], UnsameQ@@Differences[Append[#, 1]]&]], {n, 0, 30}]
CROSSREFS
Sequence in context: A350840 A176789 A308158 * A320054 A215228 A182309
KEYWORD
nonn
AUTHOR
Gus Wiseman, Apr 23 2019
STATUS
approved

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Last modified April 23 07:57 EDT 2024. Contains 371905 sequences. (Running on oeis4.)