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A344365
Numbers that are the sum of three fourth powers in exactly five ways.
6
1234349298, 1289202642, 1948502738, 2935465442, 4162186322, 5632212978, 7360969778, 8657437698, 8753497298, 11079947522, 15784025138, 17536524642, 19749588768, 20627242272, 21318234098, 31176043808, 35240346162, 37459676898, 39912730578, 42901649042
OFFSET
1,1
LINKS
EXAMPLE
1234349298 is a member of this sequence because 1234349298 = 7^4 + 154^4 + 161^4 = 26^4 + 143^4 + 169^4 = 61^4 + 118^4 + 179^4 = 74^4 + 107^4 + 181^4 = 91^4 + 91^4 + 182^4.
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, 500)]
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
KEYWORD
nonn
AUTHOR
Sean A. Irvine, May 15 2021
STATUS
approved