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.

A345833 Numbers that are the sum of eight fourth powers in exactly one ways.

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%I A345833 #6 Jul 31 2021 21:33:24
%S A345833 8,23,38,53,68,83,88,98,103,113,118,128,133,148,163,168,178,183,193,
%T A345833 198,213,228,243,248,258,328,338,353,368,403,408,418,433,468,483,488,
%U A345833 498,568,578,593,608,632,643,647,648,658,662,663,673,677,692,707,708,712
%N A345833 Numbers that are the sum of eight fourth powers in exactly one ways.
%C A345833 Differs from A003342 at term 26 because 263 = 1^4 + 1^4 + 1^4 + 1^4 + 2^4 + 3^4 + 3^4 + 3^4 = 1^4 + 1^4 + 1^4 + 1^4 + 1^4 + 1^4 + 1^4 + 4^4.
%H A345833 Sean A. Irvine, <a href="/A345833/b345833.txt">Table of n, a(n) for n = 1..10000</a>
%e A345833 23 is a term because 23 = 1^4 + 1^4 + 1^4 + 1^4 + 1^4 + 1^4 + 1^4 + 2^4.
%o A345833 (Python)
%o A345833 from itertools import combinations_with_replacement as cwr
%o A345833 from collections import defaultdict
%o A345833 keep = defaultdict(lambda: 0)
%o A345833 power_terms = [x**4 for x in range(1, 1000)]
%o A345833 for pos in cwr(power_terms, 8):
%o A345833     tot = sum(pos)
%o A345833     keep[tot] += 1
%o A345833     rets = sorted([k for k, v in keep.items() if v == 1])
%o A345833     for x in range(len(rets)):
%o A345833         print(rets[x])
%Y A345833 Cf. A003342, A345783, A345823, A345834, A345843, A346326.
%K A345833 nonn
%O A345833 1,1
%A A345833 _David Consiglio, Jr._, Jun 26 2021