A344277 Numbers that are the sum of three fourth powers in four or more ways.

5978882, 15916082, 20621042, 22673378, 30623138, 33998258, 39765362, 48432482, 53809938, 61627202, 65413922, 74346818, 84942578, 88258898, 95662112, 103363442, 117259298, 128929682, 131641538, 137149922, 143244738, 155831858, 158811842, 167042642, 174135122, 175706258, 188529362

Offset

1,1

Links

David Consiglio, Jr., Table of n, a(n) for n = 1..9084

Example

20621042 is a member of this sequence because 20621042 = 5^4 + 54^4 + 59^4 = 10^4 + 51^4 + 61^4 = 25^4 + 46^4 + 63^4 = 26^4 + 39^4 + 65^4

Prog

(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, 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 >= 4])
for x in range(len(rets)):
    print(rets[x])

Crossrefs

Cf. A343968, A344239, A344278, A344352, A344364.

Sequence in context: A183022 A183021 A343086 * A344278 A184385 A204497

Adjacent sequences: A344274 A344275 A344276 * A344278 A344279 A344280

Keyword

nonn

Author

David Consiglio, Jr., May 13 2021

Status

approved