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A344240 Numbers that are the sum of three fourth powers in exactly three ways. 6
811538, 1733522, 2798978, 3750578, 4614722, 6573938, 7303842, 8878898, 12771458, 12984608, 13760258, 14677362, 15601698, 16196193, 17868242, 21556178, 22349522, 25190802, 25589858, 27736352, 29969282, 41532498, 44048498, 44783648, 45182018, 50944418, 54894242, 57052562, 59165442, 60009248 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Differs from A344239 at term 6 because 5978882 = 3^4 + 40^4 + 43^4 = 8^4 + 37^4 + 45^4 = 15^4 + 32^4 + 47^4 = 23^4 + 25^4 + 48^4

LINKS

David Consiglio, Jr., Table of n, a(n) for n = 1..5129

EXAMPLE

2798978 is a member of this sequence because 2798978 = 6^4 + 31^4 + 37^4 = 9^4 + 29^4 + 38^4 = 13^4 + 26^4 + 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, 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

Cf. A025397, A344192, A344239, A344242, A344278.

Sequence in context: A083617 A343082 A344239 * A238522 A210060 A237790

Adjacent sequences: A344237 A344238 A344239 * A344241 A344242 A344243

KEYWORD

nonn

AUTHOR

David Consiglio, Jr., May 12 2021

STATUS

approved

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Last modified December 2 05:20 EST 2022. Contains 358485 sequences. (Running on oeis4.)