cp's OEIS Frontend

A344922 Numbers that are the sum of four fourth powers in seven or more ways.

%I A344922 #12 Jul 29 2023 13:55:46
%S A344922 6576339,13155858,16020018,16408434,22673634,23056803,26421474,
%T A344922 33734834,35965458,39786098,39803778,43583138,51071619,52652754,
%U A344922 53731458,57976083,63985314,64365939,67655779,68846274,73744563,75951138,77495778,87038883,88648914,89148114
%N A344922 Numbers that are the sum of four fourth powers in seven or more ways.
%H A344922 David Consiglio, Jr., <a href="/A344922/b344922.txt">Table of n, a(n) for n = 1..1000</a>
%e A344922 6576339 is a term because 6576339 = 1^4 + 24^4 + 41^4 + 43^4  = 3^4 + 7^4 + 41^4 + 44^4  = 4^4 + 23^4 + 27^4 + 49^4  = 6^4 + 31^4 + 41^4 + 41^4  = 7^4 + 11^4 + 36^4 + 47^4  = 7^4 + 21^4 + 28^4 + 49^4  = 12^4 + 17^4 + 29^4 + 49^4.
%o A344922 (Python)
%o A344922 from itertools import combinations_with_replacement as cwr
%o A344922 from collections import defaultdict
%o A344922 keep = defaultdict(lambda: 0)
%o A344922 power_terms = [x**4 for x in range(1, 1000)]
%o A344922 for pos in cwr(power_terms, 4):
%o A344922     tot = sum(pos)
%o A344922     keep[tot] += 1
%o A344922 rets = sorted([k for k, v in keep.items() if v == 7])
%o A344922 for x in range(len(rets)):
%o A344922     print(rets[x])
%Y A344922 Cf. A344729, A344904, A344923, A344924, A344942, A345150.
%K A344922 nonn
%O A344922 1,1
%A A344922 _David Consiglio, Jr._, Jun 02 2021