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A344904
Numbers that are the sum of four fourth powers in six or more ways.
7
3847554, 5624739, 6044418, 6576339, 6593538, 6899603, 9851058, 10456338, 11645394, 12378018, 13155858, 13638738, 16020018, 16408434, 16990803, 19081089, 20622338, 20649603, 20755218, 20795763, 22673634, 23056803, 24174003, 24368769, 25265553, 25850178
OFFSET
1,1
LINKS
David Consiglio, Jr., Table of n, a(n) for n = 1..1000
EXAMPLE
3847554 is a term because 3847554 = 2^4 + 13^4 + 29^4 + 42^4 = 2^4 + 21^4 + 22^4 + 43^4 = 6^4 + 11^4 + 17^4 + 44^4 = 6^4 + 31^4 + 32^4 + 37^4 = 9^4 + 29^4 + 32^4 + 38^4 = 13^4 + 26^4 + 32^4 + 39^4.
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, 1000)]
for pos in cwr(power_terms, 4):
tot = sum(pos)
keep[tot] += 1
rets = sorted([k for k, v in keep.items() if v >= 6])
for x in range(len(rets)):
print(rets[x])
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved