A345548 Numbers that are the sum of nine cubes in nine or more ways.

859, 861, 896, 903, 922, 929, 935, 939, 959, 966, 971, 973, 978, 985, 992, 997, 999, 1004, 1009, 1011, 1016, 1018, 1020, 1022, 1023, 1027, 1029, 1030, 1034, 1035, 1036, 1037, 1041, 1046, 1048, 1055, 1056, 1059, 1060, 1062, 1063, 1064, 1065, 1066, 1067, 1071

Offset

1,1

Links

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

Example

861 is a term because 861 = 1^3 + 1^3 + 1^3 + 1^3 + 1^3 + 1^3 + 1^3 + 4^3 + 8^3 = 1^3 + 1^3 + 1^3 + 1^3 + 1^3 + 3^3 + 3^3 + 5^3 + 7^3 = 1^3 + 1^3 + 2^3 + 2^3 + 4^3 + 4^3 + 4^3 + 4^3 + 6^3 = 1^3 + 1^3 + 3^3 + 3^3 + 3^3 + 3^3 + 3^3 + 3^3 + 7^3 = 1^3 + 2^3 + 2^3 + 2^3 + 2^3 + 2^3 + 3^3 + 3^3 + 8^3 = 1^3 + 2^3 + 2^3 + 2^3 + 3^3 + 4^3 + 4^3 + 5^3 + 6^3 = 2^3 + 2^3 + 2^3 + 2^3 + 3^3 + 3^3 + 5^3 + 5^3 + 6^3 = 2^3 + 2^3 + 2^3 + 2^3 + 3^3 + 3^3 + 3^3 + 4^3 + 7^3 = 3^3 + 3^3 + 3^3 + 3^3 + 4^3 + 4^3 + 4^3 + 4^3 + 5^3.

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

Crossrefs

Cf. A345539, A345547, A345549, A345557, A345593, A345801.

Sequence in context: A163304 A252237 A284074 * A345801 A183628 A187281

Adjacent sequences: A345545 A345546 A345547 * A345549 A345550 A345551

Keyword

nonn

Author

David Consiglio, Jr., Jun 20 2021

Status

approved