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%I #6 Jul 31 2021 19:24:27
%S 1184966816,1700336000,1717860100,1972000800,2229475325,2396275200,
%T 2548597632,2625460992,2886251808,3217068800,3697267200,3729261536,
%U 3765398725,4046532448,4165116967,4246566632,4286704224,4489548050,4539955200,4623694108,4710031469
%N Numbers that are the sum of six fifth powers in exactly seven ways.
%C Differs from A345721 at term 6 because 2295937600 = 4^5 + 21^5 + 38^5 + 42^5 + 43^5 + 72^5 = 8^5 + 16^5 + 30^5 + 42^5 + 54^5 + 70^5 = 8^5 + 13^5 + 36^5 + 37^5 + 57^5 + 69^5 = 14^5 + 16^5 + 16^5 + 52^5 + 54^5 + 68^5 = 3^5 + 14^5 + 32^5 + 44^5 + 61^5 + 66^5 = 4^5 + 18^5 + 22^5 + 52^5 + 58^5 + 66^5 = 10^5 + 14^5 + 26^5 + 42^5 + 63^5 + 65^5 = 1^5 + 7^5 + 34^5 + 57^5 + 58^5 + 63^5.
%H Sean A. Irvine, <a href="/A346362/b346362.txt">Table of n, a(n) for n = 1..2648</a>
%e 1184966816 is a term because 1184966816 = 15^5 + 24^5 + 27^5 + 38^5 + 39^5 + 63^5 = 2^5 + 28^5 + 36^5 + 36^5 + 42^5 + 62^5 = 4^5 + 24^5 + 38^5 + 38^5 + 40^5 + 62^5 = 21^5 + 32^5 + 37^5 + 41^5 + 45^5 + 60^5 = 8^5 + 14^5 + 34^5 + 40^5 + 52^5 + 58^5 = 11^5 + 17^5 + 22^5 + 49^5 + 51^5 + 56^5 = 11^5 + 16^5 + 22^5 + 52^5 + 52^5 + 53^5.
%o (Python)
%o from itertools import combinations_with_replacement as cwr
%o from collections import defaultdict
%o keep = defaultdict(lambda: 0)
%o power_terms = [x**5 for x in range(1, 1000)]
%o for pos in cwr(power_terms, 6):
%o tot = sum(pos)
%o keep[tot] += 1
%o rets = sorted([k for k, v in keep.items() if v == 7])
%o for x in range(len(rets)):
%o print(rets[x])
%Y Cf. A345721, A345819, A346284, A346361, A346363.
%K nonn
%O 1,1
%A _David Consiglio, Jr._, Jul 13 2021
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