A345718 Numbers that are the sum of six fifth powers in four or more ways.

12047994, 20646208, 21017489, 21300963, 21741819, 24993485, 27669050, 28576064, 30193856, 30785920, 35480456, 35735194, 36082750, 37303264, 39035975, 46814942, 47963291, 50047062, 50724345, 52987561, 53076800, 53606848, 54827300, 55101101, 56766906

Offset

1,1

Links

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

Example

20646208 is a term because 20646208 = 2^5 + 12^5 + 12^5 + 16^5 + 18^5 + 28^5 = 3^5 + 4^5 + 4^5 + 8^5 + 10^5 + 29^5 = 6^5 + 6^5 + 12^5 + 14^5 + 24^5 + 26^5 = 7^5 + 7^5 + 8^5 + 16^5 + 25^5 + 25^5.

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, 6):
    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])

Crossrefs

Cf. A344518, A345561, A345604, A345607, A345719, A346359.

Sequence in context: A123086 A208490 A272021 * A346359 A233634 A022227

Adjacent sequences: A345715 A345716 A345717 * A345719 A345720 A345721

Keyword

nonn

Author

David Consiglio, Jr., Jun 24 2021

Status

approved