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.

A344648 Numbers that are the sum of three fourth powers in exactly six ways.

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%I A344648 #11 Jan 04 2022 10:31:13
%S A344648 292965218,1010431058,1110995522,1500533762,1665914642,2158376402,
%T A344648 2373191618,2636686962,2689817858,3019732898,3205282178,3642994082,
%U A344648 3831800882,4324686002,4687443488,5064808658,5175310322,6317554418,6450435362,6720346178,7018992162,7635761042,7781780258
%N A344648 Numbers that are the sum of three fourth powers in exactly six ways.
%C A344648 Differs from A344647 at term 2 because 779888018 = 3^4 + 139^4 + 142^4 = 9^4 + 38^4 + 167^4 = 14^4 + 133^4 + 147^4 = 43^4 + 114^4 + 157^4 = 47^4 + 111^4 + 158^4 = 63^4 + 98^4 + 161^4 = 73^4 + 89^4 + 162^4.
%H A344648 Sean A. Irvine, <a href="/A344648/b344648.txt">Table of n, a(n) for n = 1..5000</a>
%e A344648 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 A344648 (Python)
%o A344648 from itertools import combinations_with_replacement as cwr
%o A344648 from collections import defaultdict
%o A344648 keep = defaultdict(lambda: 0)
%o A344648 power_terms = [x**4 for x in range(1, 500)]
%o A344648 for pos in cwr(power_terms, 3):
%o A344648     tot = sum(pos)
%o A344648     keep[tot] += 1
%o A344648 rets = sorted([k for k, v in keep.items() if v == 6])
%o A344648 for x in range(len(rets)):
%o A344648     print(rets[x])
%Y A344648 Cf. A344365, A344647, A344730, A344921, A345084.
%K A344648 nonn
%O A344648 1,1
%A A344648 _David Consiglio, Jr._, May 25 2021