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A325768
Number of integer partitions of n for which every restriction to a subinterval has a different sum.
20
1, 1, 1, 2, 2, 3, 3, 5, 5, 8, 7, 11, 12, 15, 15, 23, 22, 29, 32, 40, 42, 55, 56, 71, 75, 92, 100, 124, 128, 152, 167, 198, 212, 255, 269, 315, 343, 392, 428, 501, 529, 615, 665, 757, 812, 937, 1002, 1142, 1238, 1385, 1490, 1701, 1808, 2038, 2200, 2476
OFFSET
0,4
COMMENTS
Also the number of Golomb rulers of length n whose consecutive marks are separated by weakly decreasing distances.
The Heinz numbers of these partitions are given by A325779.
EXAMPLE
The a(1) = 1 through a(9) = 8 partitions:
(1) (2) (3) (4) (5) (6) (7) (8) (9)
(21) (31) (32) (42) (43) (53) (54)
(41) (51) (52) (62) (63)
(61) (71) (72)
(421) (521) (81)
(432)
(531)
(621)
MATHEMATICA
Table[Length[Select[IntegerPartitions[n], UnsameQ@@ReplaceList[#, {___, s__, ___}:>Plus[s]]&]], {n, 0, 30}]
KEYWORD
nonn
AUTHOR
Gus Wiseman, May 21 2019
STATUS
approved