A345619 Numbers that are the sum of nine fifth powers in two or more ways.

4101, 4132, 4163, 4194, 4225, 4343, 4374, 4405, 4436, 4585, 4616, 4647, 4827, 4858, 5069, 5124, 5155, 5186, 5217, 5366, 5397, 5428, 5608, 5639, 5850, 6147, 6178, 6209, 6389, 6420, 6631, 7170, 7201, 7225, 7256, 7287, 7318, 7412, 7467, 7498, 7529, 7709, 7740

Offset

1,1

Links

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

Example

4132 is a term because 4132 = 1^5 + 1^5 + 1^5 + 1^5 + 2^5 + 4^5 + 4^5 + 4^5 + 4^5 = 1^5 + 1^5 + 1^5 + 2^5 + 3^5 + 3^5 + 3^5 + 3^5 + 5^5.

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, 9):
    tot = sum(pos)
    keep[tot] += 1
    rets = sorted([k for k, v in keep.items() if v >= 2])
    for x in range(len(rets)):
        print(rets[x])

Crossrefs

Cf. A003354, A345586, A345610, A345620, A345634, A346337.

Sequence in context: A043476 A168191 A045036 * A346337 A345634 A346347

Adjacent sequences: A345616 A345617 A345618 * A345620 A345621 A345622

Keyword

nonn

Author

David Consiglio, Jr., Jun 20 2021

Status

approved