OFFSET
0,3
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..1000
EXAMPLE
The a(1) = 1 through a(7) = 11 partitions:
(1) (2) (3) (4) (5) (6) (7)
(11) (21) (22) (32) (33) (43)
(31) (41) (42) (52)
(211) (221) (51) (61)
(311) (321) (322)
(2111) (411) (331)
(2211) (421)
(3111) (511)
(2221)
(3211)
(4111)
MAPLE
b:= proc(n, i, t) option remember; `if`(n=0, `if`(t>=0, 1, 0),
`if`(i<1, 0, add(b(n-i*j, i-1, t+`if`(j>0, 2, 0)-j), j=0..n/i)))
end:
a:= n-> b(n$2, 0):
seq(a(n), n=0..50); # Alois P. Heinz, Mar 19 2023
MATHEMATICA
Table[Length[Select[IntegerPartitions[n], 2*Length[Union[#]]>=Length[#]&]], {n, 0, 30}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Gus Wiseman, Mar 17 2023
STATUS
approved