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A357849
Number of integer partitions (w,x,y) summing to n such that 2w = 3x + 4y.
4
0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 1, 1, 2, 1, 2, 2, 1, 2, 1, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 3, 2, 3, 2, 2, 3, 2, 3, 3, 2, 3, 3, 3, 3, 2, 3, 3, 3, 3, 3, 3
OFFSET
0,34
EXAMPLE
The partitions for n = 34, 64, 89, 119, 144:
(21,10,3) (39,22,3) (54,32,3) (72,44,3) (87,54,3)
(40,16,8) (55,26,8) (73,38,8) (88,48,8)
(56,20,13) (74,32,13) (89,42,13)
(75,26,18) (90,36,18)
(91,30,23)
MATHEMATICA
Table[Length[Select[IntegerPartitions[n, {3}], 2*#[[1]]==3*#[[2]]+4*#[[3]]&]], {n, 0, 100}]
PROG
(Python)
def A357849(n): return sum(1 for y in range(1, n-1) if (m:=2*n-6*y)>=5*y and 5*(n-y)>=2*m and m%5==0) # Chai Wah Wu, Nov 02 2022
CROSSREFS
Partitions are counted by A000041, strict A000009.
The ordered version appears to be A008676, ranked by A357489.
These partitions are ranked by A358102.
Sequence in context: A293451 A063014 A286361 * A097295 A220572 A083896
KEYWORD
nonn
AUTHOR
Gus Wiseman, Nov 02 2022
STATUS
approved