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.

A345580 Numbers that are the sum of eight fourth powers in five or more ways.

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%I A345580 #6 Jul 31 2021 17:51:37
%S A345580 4228,4403,4468,5443,5508,5683,6613,6643,6658,6708,6723,6773,6788,
%T A345580 6838,6853,6868,6883,6898,6948,6963,7013,7028,7093,7138,7203,7267,
%U A345580 7268,7332,7397,7478,7507,7572,7588,7828,7858,7923,7938,7988,8003,8068,8113,8133,8178
%N A345580 Numbers that are the sum of eight fourth powers in five or more ways.
%H A345580 Sean A. Irvine, <a href="/A345580/b345580.txt">Table of n, a(n) for n = 1..10000</a>
%e A345580 4403 is a term because 4403 = 1^4 + 1^4 + 1^4 + 2^4 + 2^4 + 2^4 + 4^4 + 8^4 = 1^4 + 1^4 + 1^4 + 4^4 + 4^4 + 6^4 + 6^4 + 6^4 = 2^4 + 2^4 + 2^4 + 2^4 + 3^4 + 3^4 + 3^4 + 8^4 = 2^4 + 2^4 + 3^4 + 3^4 + 4^4 + 4^4 + 6^4 + 7^4 = 2^4 + 3^4 + 3^4 + 3^4 + 4^4 + 6^4 + 6^4 + 6^4.
%o A345580 (Python)
%o A345580 from itertools import combinations_with_replacement as cwr
%o A345580 from collections import defaultdict
%o A345580 keep = defaultdict(lambda: 0)
%o A345580 power_terms = [x**4 for x in range(1, 1000)]
%o A345580 for pos in cwr(power_terms, 8):
%o A345580     tot = sum(pos)
%o A345580     keep[tot] += 1
%o A345580     rets = sorted([k for k, v in keep.items() if v >= 5])
%o A345580     for x in range(len(rets)):
%o A345580         print(rets[x])
%Y A345580 Cf. A345535, A345571, A345579, A345581, A345589, A345613, A345837.
%K A345580 nonn
%O A345580 1,1
%A A345580 _David Consiglio, Jr._, Jun 20 2021