A345606 Numbers that are the sum of seven fifth powers in three or more ways.

84457, 166997, 324860, 326199, 358482, 359327, 391007, 391999, 408158, 455146, 455749, 486468, 502429, 572054, 595519, 614505, 622280, 648319, 671210, 672022, 696468, 696499, 696710, 697491, 699592, 704243, 713274, 729235, 755516, 796467, 857518, 877645

Offset

1,1

Links

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

Example

166997 is a term because 166997 = 2^5 + 5^5 + 8^5 + 8^5 + 8^5 + 8^5 + 8^5 = 4^5 + 6^5 + 6^5 + 7^5 + 7^5 + 7^5 + 10^5 = 5^5 + 6^5 + 6^5 + 6^5 + 6^5 + 8^5 + 10^5.

Prog

(Python)
from itertools import combinations_with_replacement as cwr
from collections import defaultdict
keep = defaultdict(lambda: 0)
power_terms = [x**5 for x in range(1, 1000)]
for pos in cwr(power_terms, 7):
    tot = sum(pos)
    keep[tot] += 1
    rets = sorted([k for k, v in keep.items() if v >= 3])
    for x in range(len(rets)):
        print(rets[x])

Crossrefs

Cf. A345569, A345604, A345605, A345607, A345611, A346280.

Sequence in context: A333683 A295470 A237492 * A346280 A034604 A202615

Adjacent sequences: A345603 A345604 A345605 * A345607 A345608 A345609

Keyword

nonn

Author

David Consiglio, Jr., Jun 20 2021

Status

approved