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.

A344647 Numbers that are the sum of three fourth powers in six or more ways.

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%I A344647 #8 Jul 31 2021 18:29:15
%S A344647 292965218,779888018,1010431058,1110995522,1500533762,1665914642,
%T A344647 2158376402,2373191618,2636686962,2689817858,3019732898,3205282178,
%U A344647 3642994082,3831800882,4324686002,4687443488,5064808658,5175310322,5745705602,6317554418,6450435362,6720346178,7018992162
%N A344647 Numbers that are the sum of three fourth powers in six or more ways.
%H A344647 Sean A. Irvine, <a href="/A344647/b344647.txt">Table of n, a(n) for n = 1..10000</a> (terms 1..70 from David Consiglio, Jr.)
%e A344647 1010431058 is a term because 1010431058 = 13^4 + 143^4 + 156^4 = 31^4 + 132^4 + 163^4 = 44^4 + 123^4 + 167^4 = 52^4 + 117^4 + 169^4 = 69^4 + 103^4 + 172^4 = 81^4 + 92^4 + 173^4
%o A344647 (Python)
%o A344647 from itertools import combinations_with_replacement as cwr
%o A344647 from collections import defaultdict
%o A344647 keep = defaultdict(lambda: 0)
%o A344647 power_terms = [x**4 for x in range(1, 500)]
%o A344647 for pos in cwr(power_terms, 3):
%o A344647     tot = sum(pos)
%o A344647     keep[tot] += 1
%o A344647 rets = sorted([k for k, v in keep.items() if v >= 6])
%o A344647 for x in range(len(rets)):
%o A344647     print(rets[x])
%Y A344647 Cf. A344364, A344648, A344729, A344904, A345083.
%K A344647 nonn
%O A344647 1,1
%A A344647 _David Consiglio, Jr._, May 25 2021