OFFSET
1,1
COMMENTS
Differs from A341781 at term 3 because
954979 = 1^4 + 2^4 + 11^4 + 19^4 + 30^4
= 1^4 + 7^4 + 18^4 + 25^4 + 26^4
= 3^4 + 8^4 + 17^4 + 20^4 + 29^4
= 4^4 + 8^4 + 13^4 + 25^4 + 27^4
= 4^4 + 9^4 + 10^4 + 11^4 + 31^4
= 6^4 + 6^4 + 15^4 + 21^4 + 29^4
= 7^4 + 10^4 + 18^4 + 19^4 + 29^4
= 11^4 + 11^4 + 20^4 + 22^4 + 27^4
= 16^4 + 17^4 + 17^4 + 24^4 + 25^4
= 18^4 + 19^4 + 20^4 + 23^4 + 23^4.
LINKS
David Consiglio, Jr., Table of n, a(n) for n = 1..10000
EXAMPLE
619090 = 1^4 + 2^4 + 18^4 + 22^4 + 23^4
= 1^4 + 3^4 + 4^4 + 8^4 + 28^4
= 1^4 + 11^4 + 14^4 + 22^4 + 24^4
= 2^4 + 2^4 + 8^4 + 17^4 + 27^4
= 2^4 + 13^4 + 13^4 + 18^4 + 26^4
= 3^4 + 6^4 + 12^4 + 16^4 + 27^4
= 4^4 + 12^4 + 14^4 + 23^4 + 23^4
= 9^4 + 12^4 + 16^4 + 21^4 + 24^4
= 14^4 + 16^4 + 18^4 + 19^4 + 23^4
so 619090 is a term.
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, 5):
tot = sum(pos)
keep[tot] += 1
rets = sorted([k for k, v in keep.items() if v == 9])
for x in range(len(rets)):
print(rets[x])
CROSSREFS
KEYWORD
nonn
AUTHOR
David Consiglio, Jr., Jun 04 2021
STATUS
approved