cp's OEIS Frontend

A345620 Numbers that are the sum of nine fifth powers in three or more ways.

%I A345620 #6 Jul 31 2021 16:08:55
%S A345620 52418,52449,52660,53441,54519,54550,54761,55542,55690,57643,60193,
%T A345620 62294,69224,69635,69666,69877,70658,70955,70986,71197,71325,71978,
%U A345620 72759,73001,74079,76031,77410,78730,84162,84459,84490,84521,84701,84732,84943,85185,85482
%N A345620 Numbers that are the sum of nine fifth powers in three or more ways.
%H A345620 Sean A. Irvine, <a href="/A345620/b345620.txt">Table of n, a(n) for n = 1..10000</a>
%e A345620 52449 is a term because 52449 = 1^5 + 2^5 + 4^5 + 4^5 + 4^5 + 4^5 + 6^5 + 6^5 + 8^5 = 2^5 + 3^5 + 3^5 + 3^5 + 3^5 + 4^5 + 7^5 + 7^5 + 7^5 = 2^5 + 3^5 + 3^5 + 3^5 + 3^5 + 5^5 + 6^5 + 6^5 + 8^5.
%o A345620 (Python)
%o A345620 from itertools import combinations_with_replacement as cwr
%o A345620 from collections import defaultdict
%o A345620 keep = defaultdict(lambda: 0)
%o A345620 power_terms = [x**5 for x in range(1, 1000)]
%o A345620 for pos in cwr(power_terms, 9):
%o A345620     tot = sum(pos)
%o A345620     keep[tot] += 1
%o A345620     rets = sorted([k for k, v in keep.items() if v >= 3])
%o A345620     for x in range(len(rets)):
%o A345620         print(rets[x])
%Y A345620 Cf. A345587, A345611, A345619, A345621, A345635, A346338.
%K A345620 nonn
%O A345620 1,1
%A A345620 _David Consiglio, Jr._, Jun 20 2021