A343970 Numbers that are the sum of three positive cubes in exactly five ways.

161568, 262683, 314712, 326808, 359568, 443197, 444536, 471960, 503208, 513729, 515376, 526023, 529199, 532683, 552824, 597960, 702729, 736371, 746992, 806688, 844416, 863379, 907479, 924048, 931419, 975213, 1011067, 1028663, 1062937, 1092853, 1152152, 1172016, 1211048, 1232496, 1258011

Offset

1,1

Comments

This sequence differs from A343967 at term 40 because 1296378 = 3^3 + 76^3 + 95^3 = 9^3 + 33^3 + 108^3 = 21^3 + 77^3 + 94^3 = 31^3 + 59^3 + 102^3 = 33^3 + 81^3 + 90^3 = 60^3 + 75^3 + 87^3.

Links

David Consiglio, Jr., Table of n, a(n) for n = 1..20000

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, 50)]
for pos in cwr(power_terms, 3):
    tot = sum(pos)
    keep[tot] += 1
rets = sorted([k for k, v in keep.items() if v == 5])
for x in range(len(rets)):
    print(rets[x])

Crossrefs

Cf. A025325, A343967, A343969, A343986, A344365, A345084.

Sequence in context: A339498 A249880 A343967 * A349774 A184474 A114669

Adjacent sequences: A343967 A343968 A343969 * A343971 A343972 A343973

Keyword

nonn

Author

David Consiglio, Jr., May 05 2021

Status

approved