A343989 - OEIS

%I #14 May 10 2024 02:20:49

%S 1765,1980,2043,2104,2195,2250,2430,2449,2486,2491,2493,2547,2584,

%T 2592,2738,2745,2764,2817,2888,2915,2953,2969,2979,3095,3096,3133,

%U 3142,3186,3188,3214,3240,3249,3275,3277,3310,3312,3366,3403,3422,3459,3464,3466,3483,3492,3520,3529,3583,3608,3627,3653,3664,3671

%N Numbers that are the sum of five positive cubes in five or more ways.

%H David Consiglio, Jr., <a href="/A343989/b343989.txt">Table of n, a(n) for n = 1..20000</a>

%e 2043 = 1^3 + 4^3 + 5^3 +  5^3 + 12^3

%e      = 2^3 + 2^3 + 3^3 + 10^3 + 10^3

%e      = 2^3 + 3^3 + 4^3 +  6^3 + 12^3

%e      = 4^3 + 5^3 + 5^3 +  9^3 + 10^3

%e      = 4^3 + 6^3 + 6^3 +  6^3 + 11^3

%e so 2043 is a term.

%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**3 for x in range(1,50)]

%o for pos in cwr(power_terms,5):

%o     tot = sum(pos)

%o     keep[tot] += 1

%o rets = sorted([k for k,v in keep.items() if v >= 5])

%o for x in range(len(rets)):

%o     print(rets[x])

%Y Cf. A343987, A343988, A344034, A344358, A344798, A345174, A345514.

%K nonn

%O 1,1

%A _David Consiglio, Jr._, May 06 2021