cp's OEIS Frontend

A344240 Numbers that are the sum of three fourth powers in exactly three ways.

%I A344240 #8 Jul 31 2021 22:17:13
%S A344240 811538,1733522,2798978,3750578,4614722,6573938,7303842,8878898,
%T A344240 12771458,12984608,13760258,14677362,15601698,16196193,17868242,
%U A344240 21556178,22349522,25190802,25589858,27736352,29969282,41532498,44048498,44783648,45182018,50944418,54894242,57052562,59165442,60009248
%N A344240 Numbers that are the sum of three fourth powers in exactly three ways.
%C A344240 Differs from A344239 at term 6 because 5978882 = 3^4 + 40^4 + 43^4 = 8^4 + 37^4 + 45^4 = 15^4 + 32^4 + 47^4 = 23^4 + 25^4 + 48^4
%H A344240 David Consiglio, Jr., <a href="/A344240/b344240.txt">Table of n, a(n) for n = 1..5129</a>
%e A344240 2798978 is a member of this sequence because 2798978 = 6^4 + 31^4 + 37^4 = 9^4 + 29^4 + 38^4 = 13^4 + 26^4 + 39^4
%o A344240 (Python)
%o A344240 from itertools import combinations_with_replacement as cwr
%o A344240 from collections import defaultdict
%o A344240 keep = defaultdict(lambda: 0)
%o A344240 power_terms = [x**4 for x in range(1,50)]
%o A344240 for pos in cwr(power_terms,3):
%o A344240     tot = sum(pos)
%o A344240     keep[tot] += 1
%o A344240 rets = sorted([k for k,v in keep.items() if v == 3])
%o A344240 for x in range(len(rets)):
%o A344240     print(rets[x])
%Y A344240 Cf. A025397, A344192, A344239, A344242, A344278.
%K A344240 nonn
%O A344240 1,1
%A A344240 _David Consiglio, Jr._, May 12 2021