cp's OEIS Frontend

A345525 Numbers that are the sum of seven cubes in seven or more ways.

%I A345525 #7 Aug 05 2021 15:22:32
%S A345525 1072,1170,1235,1261,1268,1305,1385,1392,1396,1411,1440,1441,1448,
%T A345525 1450,1459,1489,1496,1502,1504,1513,1515,1538,1540,1547,1552,1557,
%U A345525 1559,1564,1565,1566,1567,1576,1585,1587,1592,1593,1594,1600,1602,1603,1606,1613,1620
%N A345525 Numbers that are the sum of seven cubes in seven or more ways.
%H A345525 Sean A. Irvine, <a href="/A345525/b345525.txt">Table of n, a(n) for n = 1..10000</a>
%e A345525 1170 is a term because 1170 = 1^3 + 1^3 + 2^3 + 2^3 + 3^3 + 4^3 + 9^3 = 1^3 + 1^3 + 2^3 + 5^3 + 5^3 + 5^3 + 7^3 = 1^3 + 1^3 + 3^3 + 4^3 + 4^3 + 4^3 + 8^3 = 1^3 + 2^3 + 3^3 + 3^3 + 4^3 + 5^3 + 8^3 = 1^3 + 3^3 + 3^3 + 3^3 + 3^3 + 7^3 + 7^3 = 3^3 + 3^3 + 4^3 + 5^3 + 5^3 + 5^3 + 6^3 = 3^3 + 3^3 + 3^3 + 4^3 + 4^3 + 5^3 + 7^3.
%o A345525 (Python)
%o A345525 from itertools import combinations_with_replacement as cwr
%o A345525 from collections import defaultdict
%o A345525 keep = defaultdict(lambda: 0)
%o A345525 power_terms = [x**3 for x in range(1, 1000)]
%o A345525 for pos in cwr(power_terms, 7):
%o A345525     tot = sum(pos)
%o A345525     keep[tot] += 1
%o A345525     rets = sorted([k for k, v in keep.items() if v >= 7])
%o A345525     for x in range(len(rets)):
%o A345525         print(rets[x])
%Y A345525 Cf. A345484, A345516, A345524, A345526, A345537, A345573, A345779.
%K A345525 nonn
%O A345525 1,1
%A A345525 _David Consiglio, Jr._, Jun 20 2021