A345540 Numbers that are the sum of eight cubes in ten or more ways.

1185, 1243, 1262, 1288, 1295, 1299, 1386, 1393, 1397, 1400, 1412, 1419, 1423, 1448, 1449, 1451, 1458, 1460, 1464, 1467, 1475, 1477, 1497, 1501, 1503, 1504, 1505, 1512, 1513, 1514, 1516, 1521, 1523, 1539, 1540, 1541, 1542, 1553, 1558, 1559, 1560, 1565, 1566

Offset

1,1

Links

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

Example

1243 is a term because 1243 = 1^3 + 1^3 + 1^3 + 2^3 + 2^3 + 2^3 + 5^3 + 9^3 = 1^3 + 1^3 + 1^3 + 3^3 + 3^3 + 4^3 + 7^3 + 7^3 = 1^3 + 1^3 + 2^3 + 2^3 + 3^3 + 6^3 + 6^3 + 7^3 = 1^3 + 1^3 + 2^3 + 2^3 + 3^3 + 5^3 + 5^3 + 8^3 = 1^3 + 1^3 + 4^3 + 4^3 + 5^3 + 5^3 + 5^3 + 6^3 = 1^3 + 2^3 + 3^3 + 5^3 + 5^3 + 5^3 + 5^3 + 6^3 = 2^3 + 2^3 + 2^3 + 3^3 + 3^3 + 3^3 + 3^3 + 9^3 = 2^3 + 3^3 + 3^3 + 3^3 + 4^3 + 6^3 + 6^3 + 6^3 = 2^3 + 3^3 + 3^3 + 3^3 + 3^3 + 4^3 + 4^3 + 8^3 = 3^3 + 3^3 + 3^3 + 3^3 + 3^3 + 5^3 + 6^3 + 7^3.

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, 8):
    tot = sum(pos)
    keep[tot] += 1
    rets = sorted([k for k, v in keep.items() if v >= 10])
    for x in range(len(rets)):
        print(rets[x])

Crossrefs

Cf. A345497, A345506, A345539, A345549, A345585, A345792.

Sequence in context: A328064 A280516 A205994 * A345792 A237698 A345664

Adjacent sequences: A345537 A345538 A345539 * A345541 A345542 A345543

Keyword

nonn

Author

David Consiglio, Jr., Jun 20 2021

Status

approved