A345086 Numbers that are the sum of three third powers in seven or more ways.

2016496, 2562624, 4525632, 4783680, 5268024, 5618250, 6366816, 6525000, 6755328, 7374375, 7451352, 7457120, 8275392, 9063144, 9086104, 9931167, 10036872, 10266138, 10371024, 10973880, 12002472, 12452049, 12742920, 12983517, 13581352, 13639816, 13641480

Offset

1,1

Links

David Consiglio, Jr., Table of n, a(n) for n = 1..100

Example

2016496 is a term because 2016496 = 5^3 + 71^3 + 117^3 = 9^3 + 65^3 + 119^3 = 18^3 + 20^3 + 125^3 = 46^3 + 96^3 + 99^3 = 53^3 + 59^3 + 117^3 = 65^3 + 89^3 + 99^3 = 82^3 + 84^3 + 93^3.

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, 3):
    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. A025335, A344729, A345083, A345085, A345087, A345150.

Sequence in context: A359534 A081398 A022226 * A345085 A032754 A271768

Adjacent sequences: A345083 A345084 A345085 * A345087 A345088 A345089

Keyword

nonn

Author

David Consiglio, Jr., Jun 07 2021

Status

approved