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A317388
a(n) is the smallest number having at least n partitions into n parts with the same product.
1
39, 24, 25, 26, 28, 30, 31, 34, 35, 37, 39, 41, 43, 44, 46, 48, 49, 51, 52, 53, 54, 56, 57, 58, 60, 61, 62, 63, 65, 66, 68, 69, 70, 72, 73, 74, 76, 77, 79, 80, 81, 83, 84, 85, 86, 87, 88, 89, 90, 92, 93, 94, 95, 96, 98, 99, 100, 101, 102, 103, 105, 106, 107, 108
OFFSET
3,1
LINKS
Byungchul Cha et al., An Investigation on Partitions with Equal Products, arXiv:1811.07451 [math.NT], 2018.
EXAMPLE
a(4) = 24 because 24 is the smallest number which admits 4 partitions in 4 parts with the same product:
24 = 12+5+4+3 = 10+8+3+3 = 10+6+6+2 = 9+8+5+2, and
720 = 12*5*4*3 = 10*8*3*3 = 10*6*6*2 = 9*8*5*2.
MATHEMATICA
a[n_] := Block[{k=n}, While[Max[Last /@ Tally[Times @@@ IntegerPartitions[k, {n}]]] < n, k++]; k]; Array[a, 40, 3]
CROSSREFS
Cf. A119028.
Sequence in context: A326791 A374870 A268854 * A088344 A268856 A273597
KEYWORD
nonn
AUTHOR
Giovanni Resta, Jul 27 2018
STATUS
approved