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A344239
Numbers that are the sum of three fourth powers in three or more ways.
6
811538, 1733522, 2798978, 3750578, 4614722, 5978882, 6573938, 7303842, 8878898, 12771458, 12984608, 13760258, 14677362, 15601698, 15916082, 16196193, 17868242, 20621042, 21556178, 22349522, 22673378, 25190802, 25589858, 27736352, 29969282, 30623138, 33998258, 39765362, 41532498, 44048498
OFFSET
1,1
LINKS
David Consiglio, Jr., Table of n, a(n) for n = 1..14213
EXAMPLE
2798978 = 6^4 + 31^4 + 37^4
= 9^4 + 29^4 + 38^4
= 13^4 + 26^4 + 39^4
so 2798978 is a term of this sequence.
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 >= 3])
for x in range(len(rets)):
print(rets[x])
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved