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.

A344641 Numbers that are the sum of three positive fifth powers in exactly one way.

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%I A344641 #13 Dec 28 2024 10:21:57
%S A344641 3,34,65,96,245,276,307,487,518,729,1026,1057,1088,1268,1299,1510,
%T A344641 2049,2080,2291,3072,3127,3158,3189,3369,3400,3611,4150,4181,4392,
%U A344641 5173,6251,6282,6493,7274,7778,7809,7840,8020,8051,8262,8801,8832,9043,9375,9824,10902,10933,11144,11925,14026,15553,15584,15795
%N A344641 Numbers that are the sum of three positive fifth powers in exactly one way.
%C A344641 Differs from A003348 at term 44785 because 1375298099 = 3^5 + 54^5 + 62^5 = 24^5 + 28^5 + 67^5. [Corrected by _Patrick De Geest_, Dec 27 2024]
%H A344641 David Consiglio, Jr., <a href="/A344641/b344641.txt">Table of n, a(n) for n = 1..20000</a>
%e A344641 65 is a term because 65 = 1^5 + 2^5 + 2^5.
%o A344641 (Python)
%o A344641 from itertools import combinations_with_replacement as cwr
%o A344641 from collections import defaultdict
%o A344641 keep = defaultdict(lambda: 0)
%o A344641 power_terms = [x**5 for x in range(1, 500)]
%o A344641 for pos in cwr(power_terms, 3):
%o A344641     tot = sum(pos)
%o A344641     keep[tot] += 1
%o A344641 rets = sorted([k for k, v in keep.items() if v == 1])
%o A344641 for x in range(len(rets)):
%o A344641     print(rets[x])
%Y A344641 Cf. A003348, A344188, A344642.
%K A344641 nonn
%O A344641 1,1
%A A344641 _David Consiglio, Jr._, May 25 2021