A345552 - OEIS

A345552

Numbers that are the sum of ten cubes in four or more ways.

225, 232, 251, 258, 265, 272, 284, 286, 288, 291, 307, 310, 314, 321, 323, 328, 342, 347, 349, 356, 363, 366, 373, 375, 377, 380, 382, 384, 389, 391, 398, 399, 401, 403, 405, 408, 410, 412, 414, 415, 417, 419, 421, 422, 424, 427, 429, 434, 436, 438, 440, 441

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

LINKS

Sean A. Irvine, Table of n, a(n) for n = 1..10000

EXAMPLE

232 is a term because 232 = 1^3 + 1^3 + 1^3 + 1^3 + 1^3 + 1^3 + 1^3 + 1^3 + 2^3 + 5^3 = 1^3 + 1^3 + 1^3 + 1^3 + 1^3 + 2^3 + 3^3 + 3^3 + 3^3 + 3^3 = 1^3 + 1^3 + 1^3 + 2^3 + 2^3 + 2^3 + 2^3 + 2^3 + 3^3 + 4^3 = 2^3 + 2^3 + 3^3 + 3^3 + 3^3 + 3^3 + 3^3 + 3^3 + 3^3 + 3^3.

PROG

(Python)

from itertools import combinations_with_replacement as cwr

from collections import defaultdict

keep = defaultdict(lambda: 0)

power_terms = [x**3 for x in range(1, 1000)]

for pos in cwr(power_terms, 10):

tot = sum(pos)

keep[tot] += 1

rets = sorted([k for k, v in keep.items() if v >= 4])

for x in range(len(rets)):

print(rets[x])