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A343967
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Numbers that are the sum of three positive cubes in five or more ways.
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9
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161568, 262683, 314712, 326808, 359568, 443197, 444536, 471960, 503208, 513729, 515376, 526023, 529199, 532683, 552824, 597960, 702729, 736371, 746992, 806688, 844416, 863379, 907479, 924048, 931419, 975213, 1011067, 1028663, 1062937, 1092853, 1152152, 1172016, 1211048, 1232496, 1258011
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OFFSET
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1,1
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LINKS
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EXAMPLE
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314712 = 4^3 + 6^3 + 68^3
= 5^3 + 24^3 + 67^3
= 6^3 + 30^3 + 66^3
= 31^3 + 41^3 + 60^3
= 36^3 + 48^3 + 54^3
so 314712 is a term of this sequence.
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PROG
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(Python)
from itertools import combinations_with_replacement as cwr
from collections import defaultdict
keep = defaultdict(lambda: 0)
power_terms = [x**3 for x in range(1, 50)]
for pos in cwr(power_terms, 3):
tot = sum(pos)
keep[tot] += 1
rets = sorted([k for k, v in keep.items() if v >= 5])
for x in range(len(rets)):
print(rets[x])
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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