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A344519
Numbers that are the sum of five fifth powers in exactly four ways.
6
287618651, 1386406515, 1763135232, 2494769760, 2619898293, 3096064443, 3291315732, 3749564512, 4045994624, 5142310350, 5183605813, 5658934676, 5880926107, 7205217018, 7401155424, 7691215599, 8429499101, 8926086432, 9051501568, 9203796832, 9254212901
OFFSET
1,1
COMMENTS
Differs from A344518 at term 20 because 9006349824 = 8^5 + 34^5 + 62^5 + 68^5 + 92^5 = 8^5 + 41^5 + 47^5 + 79^5 + 89^5 = 12^5 + 18^5 + 72^5 + 78^5 + 84^5 = 21^5 + 34^5 + 43^5 + 74^5 + 92^5 = 24^5 + 42^5 + 48^5 + 54^5 + 96^5.
LINKS
EXAMPLE
287618651 is a term because 287618651 = 9^5 + 22^5 + 28^5 + 28^5 + 49^5 = 10^5 + 14^5 + 27^5 + 38^5 + 47^5 = 12^5 + 13^5 + 24^5 + 42^5 + 45^5 = 12^5 + 21^5 + 23^5 + 31^5 + 49^5
PROG
(Python)
from itertools import combinations_with_replacement as cwr
from collections import defaultdict
keep = defaultdict(lambda: 0)
power_terms = [x**5 for x in range(1, 500)]
for pos in cwr(power_terms, 5):
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
KEYWORD
nonn
AUTHOR
STATUS
approved