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A345083
Numbers that are the sum of three third powers in six or more ways.
7
1296378, 1371735, 1409400, 1614185, 1824040, 1885248, 2016496, 2101464, 2302028, 2305395, 2542968, 2562624, 2851848, 2889216, 2974392, 2988441, 3185792, 3380833, 3681280, 3689496, 3706984, 3775680, 3906657, 4109832, 4123008, 4142683, 4422592, 4525632, 4783680
OFFSET
1,1
LINKS
David Consiglio, Jr., Table of n, a(n) for n = 1..1000
EXAMPLE
1296378 is a term because 1296378 = 3^3 + 75^3 + 94^3 = 8^3 + 32^3 + 107^3 = 20^3 + 76^3 + 93^3 = 30^3 + 58^3 + 101^3 = 32^3 + 80^3 + 89^3 = 59^3 + 74^3 + 86^3.
PROG
(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, 1000)]
for pos in cwr(power_terms, 3):
tot = sum(pos)
keep[tot] += 1
rets = sorted([k for k, v in keep.items() if v >= 6])
for x in range(len(rets)):
print(rets[x])
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved