cp's OEIS Frontend

A345860 Numbers that are the sum of ten fourth powers in exactly eight ways.

%I A345860 #6 Jul 31 2021 20:00:27
%S A345860 6675,6740,6755,6805,6995,7015,7030,7045,7095,7270,7300,7365,7429,
%T A345860 7494,7525,7540,7590,7605,7750,7780,7845,7955,8005,8085,8150,8195,
%U A345860 8215,8310,8450,8470,8500,8630,8644,8709,8710,8790,8885,8949,9124,9189,9190,9250,9255
%N A345860 Numbers that are the sum of ten fourth powers in exactly eight ways.
%C A345860 Differs from A345601 at term 5 because 6820 = 1^4 + 1^4 + 1^4 + 2^4 + 2^4 + 2^4 + 2^4 + 4^4 + 7^4 + 8^4  = 1^4 + 1^4 + 1^4 + 2^4 + 2^4 + 2^4 + 3^4 + 6^4 + 6^4 + 8^4  = 1^4 + 1^4 + 1^4 + 2^4 + 4^4 + 4^4 + 6^4 + 6^4 + 6^4 + 7^4  = 1^4 + 1^4 + 1^4 + 3^4 + 4^4 + 6^4 + 6^4 + 6^4 + 6^4 + 6^4  = 1^4 + 2^4 + 2^4 + 2^4 + 2^4 + 2^4 + 2^4 + 3^4 + 3^4 + 9^4  = 2^4 + 2^4 + 2^4 + 2^4 + 2^4 + 3^4 + 3^4 + 3^4 + 7^4 + 8^4  = 2^4 + 2^4 + 2^4 + 3^4 + 3^4 + 4^4 + 4^4 + 6^4 + 7^4 + 7^4  = 2^4 + 2^4 + 3^4 + 3^4 + 3^4 + 4^4 + 6^4 + 6^4 + 6^4 + 7^4  = 2^4 + 3^4 + 3^4 + 3^4 + 3^4 + 6^4 + 6^4 + 6^4 + 6^4 + 6^4.
%H A345860 Sean A. Irvine, <a href="/A345860/b345860.txt">Table of n, a(n) for n = 1..8900</a>
%e A345860 6740 is a term because 6740 = 1^4 + 1^4 + 1^4 + 1^4 + 2^4 + 2^4 + 2^4 + 6^4 + 6^4 + 8^4 = 1^4 + 1^4 + 1^4 + 1^4 + 4^4 + 6^4 + 6^4 + 6^4 + 6^4 + 6^4 = 1^4 + 1^4 + 2^4 + 2^4 + 2^4 + 2^4 + 2^4 + 2^4 + 3^4 + 9^4 = 1^4 + 2^4 + 2^4 + 2^4 + 2^4 + 2^4 + 3^4 + 3^4 + 7^4 + 8^4 = 1^4 + 2^4 + 2^4 + 2^4 + 3^4 + 4^4 + 4^4 + 6^4 + 7^4 + 7^4 = 1^4 + 2^4 + 2^4 + 3^4 + 3^4 + 4^4 + 6^4 + 6^4 + 6^4 + 7^4 = 1^4 + 2^4 + 3^4 + 3^4 + 3^4 + 6^4 + 6^4 + 6^4 + 6^4 + 6^4 = 3^4 + 3^4 + 3^4 + 3^4 + 4^4 + 4^4 + 4^4 + 4^4 + 6^4 + 8^4.
%o A345860 (Python)
%o A345860 from itertools import combinations_with_replacement as cwr
%o A345860 from collections import defaultdict
%o A345860 keep = defaultdict(lambda: 0)
%o A345860 power_terms = [x**4 for x in range(1, 1000)]
%o A345860 for pos in cwr(power_terms, 10):
%o A345860     tot = sum(pos)
%o A345860     keep[tot] += 1
%o A345860     rets = sorted([k for k, v in keep.items() if v == 8])
%o A345860     for x in range(len(rets)):
%o A345860         print(rets[x])
%Y A345860 Cf. A345601, A345810, A345850, A345859, A345861, A346353.
%K A345860 nonn
%O A345860 1,1
%A A345860 _David Consiglio, Jr._, Jun 26 2021