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A345150 Numbers that are the sum of four third powers in seven or more ways. 8
13104, 18928, 19376, 20755, 21203, 21896, 22743, 24544, 24570, 24787, 25172, 25928, 27720, 27755, 27846, 28917, 29582, 30429, 31031, 31248, 31339, 31402, 31528, 32858, 33579, 34056, 34624, 34713, 34776, 35289, 35317, 35441, 35497, 35712, 36162, 36190, 36225 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

David Consiglio, Jr., Table of n, a(n) for n = 1..10000

EXAMPLE

13104 is a term because 13104 = 1^3 + 10^3 + 16^3 + 18^3  = 1^3 + 11^3 + 14^3 + 19^3  = 2^3 + 9^3 + 15^3 + 19^3  = 4^3 + 6^3 + 14^3 + 20^3  = 4^3 + 9^3 + 10^3 + 21^3  = 5^3 + 7^3 + 11^3 + 21^3  = 8^3 + 9^3 + 14^3 + 19^3.

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, 4):

    tot = sum(pos)

    keep[tot] += 1

rets = sorted([k for k, v in keep.items() if v >= 7])

for x in range(len(rets)):

    print(rets[x])

CROSSREFS

Cf. A025372, A344922, A345086, A345148, A345151, A345152, A345180.

Sequence in context: A249495 A235335 A184768 * A345151 A252548 A015341

Adjacent sequences:  A345147 A345148 A345149 * A345151 A345152 A345153

KEYWORD

nonn

AUTHOR

David Consiglio, Jr., Jun 09 2021

STATUS

approved

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Last modified November 28 22:01 EST 2021. Contains 349415 sequences. (Running on oeis4.)