A345148 Numbers that are the sum of four third powers in six or more ways.

6883, 12411, 13104, 13923, 14112, 14581, 14896, 14904, 15561, 15876, 16317, 16640, 17208, 17479, 17992, 18739, 18865, 18928, 19035, 19080, 19376, 19665, 19712, 19763, 19880, 20007, 20384, 20755, 20979, 21203, 21231, 21420, 21707, 21896, 22409, 22617, 22743

Offset

1,1

Links

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

Example

6883 is a term because 6883 = 2^3 + 2^3 + 2^3 + 18^3  = 2^3 + 4^3 + 14^3 + 14^3  = 3^3 + 7^3 + 7^3 + 17^3  = 3^3 + 10^3 + 13^3 + 13^3  = 4^3 + 10^3 + 10^3 + 15^3  = 7^3 + 8^3 + 8^3 + 16^3.

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 >= 6])
for x in range(len(rets)):
    print(rets[x])

Crossrefs

Cf. A025371, A343987, A344904, A345083, A345149, A345150, A345174.

Sequence in context: A154086 A064351 A366205 * A345149 A345603 A345862

Adjacent sequences: A345145 A345146 A345147 * A345149 A345150 A345151

Keyword

nonn

Author

David Consiglio, Jr., Jun 09 2021

Status

approved