cp's OEIS Frontend

A345523 Numbers that are the sum of seven cubes in five or more ways.

%I A345523 #7 Aug 05 2021 15:22:25
%S A345523 627,768,838,845,857,864,874,881,894,900,920,937,950,955,962,969,976,
%T A345523 981,983,990,1002,1009,1011,1016,1027,1046,1053,1054,1060,1061,1063,
%U A345523 1072,1079,1089,1096,1098,1102,1105,1107,1109,1115,1117,1121,1124,1128,1133
%N A345523 Numbers that are the sum of seven cubes in five or more ways.
%H A345523 Sean A. Irvine, <a href="/A345523/b345523.txt">Table of n, a(n) for n = 1..10000</a>
%e A345523 768 is a term because 768 = 1^3 + 1^3 + 1^3 + 1^3 + 2^3 + 3^3 + 8^3 = 1^3 + 1^3 + 1^3 + 3^3 + 3^3 + 4^3 + 7^3 = 1^3 + 1^3 + 2^3 + 2^3 + 3^3 + 6^3 + 6^3 = 2^3 + 2^3 + 2^3 + 2^3 + 2^3 + 5^3 + 7^3 = 3^3 + 3^3 + 3^3 + 3^3 + 3^3 + 5^3 + 6^3.
%o A345523 (Python)
%o A345523 from itertools import combinations_with_replacement as cwr
%o A345523 from collections import defaultdict
%o A345523 keep = defaultdict(lambda: 0)
%o A345523 power_terms = [x**3 for x in range(1, 1000)]
%o A345523 for pos in cwr(power_terms, 7):
%o A345523     tot = sum(pos)
%o A345523     keep[tot] += 1
%o A345523     rets = sorted([k for k, v in keep.items() if v >= 5])
%o A345523     for x in range(len(rets)):
%o A345523         print(rets[x])
%Y A345523 Cf. A345482, A345514, A345522, A345524, A345535, A345571, A345777.
%K A345523 nonn
%O A345523 1,1
%A A345523 _David Consiglio, Jr._, Jun 20 2021