cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A344241 Numbers that are the sum of four fourth powers in three or more ways.

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%I A344241 #12 May 10 2024 02:20:13
%S A344241 16578,43234,49329,53218,54978,57154,93393,106354,107649,108754,
%T A344241 138258,151219,160434,168963,173539,177699,178738,181138,183603,
%U A344241 185298,195378,195859,196418,197154,197778,201683,202419,209763,211249,216594,217138,223074,234274,235554,235569,236674,237249,237699
%N A344241 Numbers that are the sum of four fourth powers in three or more ways.
%H A344241 David Consiglio, Jr., <a href="/A344241/b344241.txt">Table of n, a(n) for n = 1..20000</a>
%e A344241 49329 = 2^4 + 2^4 + 12^4 + 13^4
%e A344241       = 4^4 + 8^4 +  9^4 + 14^4
%e A344241       = 6^4 + 9^4 + 12^4 + 12^4
%e A344241 so 49329 is a term of this sequence.
%o A344241 (Python)
%o A344241 from itertools import combinations_with_replacement as cwr
%o A344241 from collections import defaultdict
%o A344241 keep = defaultdict(lambda: 0)
%o A344241 power_terms = [x**4 for x in range(1,50)]
%o A344241 for pos in cwr(power_terms,4):
%o A344241     tot = sum(pos)
%o A344241     keep[tot] += 1
%o A344241 rets = sorted([k for k,v in keep.items() if v >= 3])
%o A344241 for x in range(len(rets)):
%o A344241     print(rets[x])
%Y A344241 Cf. A025407, A309763, A344239, A344242, A344243, A344352, A345337.
%K A344241 nonn
%O A344241 1,1
%A A344241 _David Consiglio, Jr._, May 12 2021