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Numbers that are the sum of three positive cubes in exactly five ways.
6

%I #9 Jul 31 2021 23:41:31

%S 161568,262683,314712,326808,359568,443197,444536,471960,503208,

%T 513729,515376,526023,529199,532683,552824,597960,702729,736371,

%U 746992,806688,844416,863379,907479,924048,931419,975213,1011067,1028663,1062937,1092853,1152152,1172016,1211048,1232496,1258011

%N Numbers that are the sum of three positive cubes in exactly five ways.

%C This sequence differs from A343967 at term 40 because 1296378 = 3^3 + 76^3 + 95^3 = 9^3 + 33^3 + 108^3 = 21^3 + 77^3 + 94^3 = 31^3 + 59^3 + 102^3 = 33^3 + 81^3 + 90^3 = 60^3 + 75^3 + 87^3.

%H David Consiglio, Jr., <a href="/A343970/b343970.txt">Table of n, a(n) for n = 1..20000</a>

%o (Python)

%o from itertools import combinations_with_replacement as cwr

%o from collections import defaultdict

%o keep = defaultdict(lambda: 0)

%o power_terms = [x**3 for x in range(1,50)]

%o for pos in cwr(power_terms,3):

%o tot = sum(pos)

%o keep[tot] += 1

%o rets = sorted([k for k,v in keep.items() if v == 5])

%o for x in range(len(rets)):

%o print(rets[x])

%Y Cf. A025325, A343967, A343969, A343986, A344365, A345084.

%K nonn

%O 1,1

%A _David Consiglio, Jr._, May 05 2021