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A344642
Numbers that are the sum of four fifth powers in exactly one way.
6
4, 35, 66, 97, 128, 246, 277, 308, 339, 488, 519, 550, 730, 761, 972, 1027, 1058, 1089, 1120, 1269, 1300, 1331, 1511, 1542, 1753, 2050, 2081, 2112, 2292, 2323, 2534, 3073, 3104, 3128, 3159, 3190, 3221, 3315, 3370, 3401, 3432, 3612, 3643, 3854, 4096, 4151, 4182, 4213, 4393, 4424, 4635, 5174, 5205, 5416, 6197, 6252
OFFSET
1,1
COMMENTS
Differs from A003349 at term 270 because 51445 = 4^5 + 8^5 + 8^5 + 8^5 = 6^5 + 7^5 + 7^5 + 9^5
LINKS
David Consiglio, Jr., Table of n, a(n) for n = 1..20000
EXAMPLE
66 is a term because 66 = 1^5 + 1^5 + 2^5 + 2^5
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, 4):
tot = sum(pos)
keep[tot] += 1
rets = sorted([k for k, v in keep.items() if v == 1])
for x in range(len(rets)):
print(rets[x])
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved