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.

A345597 Numbers that are the sum of ten fourth powers in four or more ways.

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%I A345597 #6 Jul 31 2021 17:25:47
%S A345597 1620,2660,2725,2740,2835,2855,2870,2900,2915,2920,2935,2950,2965,
%T A345597 2980,3000,3015,3030,3045,3095,3110,3160,3175,3190,3205,3220,3240,
%U A345597 3255,3270,3285,3335,3350,3415,3430,3445,3460,3479,3510,3525,3544,3559,3574,3589,3639
%N A345597 Numbers that are the sum of ten fourth powers in four or more ways.
%H A345597 Sean A. Irvine, <a href="/A345597/b345597.txt">Table of n, a(n) for n = 1..10000</a>
%e A345597 2660 is a term because 2660 = 1^4 + 1^4 + 1^4 + 1^4 + 2^4 + 2^4 + 2^4 + 2^4 + 6^4 + 6^4 = 1^4 + 1^4 + 1^4 + 3^4 + 4^4 + 4^4 + 4^4 + 4^4 + 4^4 + 6^4 = 1^4 + 2^4 + 2^4 + 2^4 + 2^4 + 2^4 + 2^4 + 3^4 + 3^4 + 7^4 = 2^4 + 3^4 + 3^4 + 3^4 + 3^4 + 4^4 + 4^4 + 4^4 + 4^4 + 6^4.
%o A345597 (Python)
%o A345597 from itertools import combinations_with_replacement as cwr
%o A345597 from collections import defaultdict
%o A345597 keep = defaultdict(lambda: 0)
%o A345597 power_terms = [x**4 for x in range(1, 1000)]
%o A345597 for pos in cwr(power_terms, 10):
%o A345597     tot = sum(pos)
%o A345597     keep[tot] += 1
%o A345597     rets = sorted([k for k, v in keep.items() if v >= 4])
%o A345597     for x in range(len(rets)):
%o A345597         print(rets[x])
%Y A345597 Cf. A345552, A345588, A345596, A345598, A345636, A345856.
%K A345597 nonn
%O A345597 1,1
%A A345597 _David Consiglio, Jr._, Jun 20 2021