A344942 Numbers that are the sum of five fourth powers in seven or more ways.

197779, 211059, 217154, 236675, 431155, 444019, 480739, 503539, 530659, 534130, 548994, 564979, 568450, 571539, 602450, 602770, 619090, 621859, 625635, 625939, 626194, 650659, 651954, 653059, 654130, 654754, 663155, 666739, 687314, 692754, 692899, 698019

Offset: 1

Author

David Consiglio, Jr., Jun 03 2021

Keywords

• nonn

Examples

			197779 is a term because 197779 = 1^4 + 5^4 + 6^4 + 16^4 + 19^4  = 1^4 + 7^4 + 11^4 + 12^4 + 20^4  = 1^4 + 10^4 + 12^4 + 17^4 + 17^4  = 2^4 + 4^4 + 5^4 + 7^4 + 21^4  = 3^4 + 5^4 + 6^4 + 6^4 + 21^4  = 4^4 + 7^4 + 9^4 + 13^4 + 20^4  = 11^4 + 13^4 + 14^4 + 15^4 + 16^4.
		

Links

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

Crossrefs

Cf. A344922, A344940, A344943, A344944, A345180, A345564.

Programs

Python

from itertools import combinations_with_replacement as cwr
from collections import defaultdict
keep = defaultdict(lambda: 0)
power_terms = [x**4 for x in range(1, 1000)]
for pos in cwr(power_terms, 5):
    tot = sum(pos)
    keep[tot] += 1
rets = sorted([k for k, v in keep.items() if v >= 7])
for x in range(len(rets)):
    print(rets[x])