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A344187 Numbers that are the sum of two positive fourth powers in exactly one way. 6
2, 17, 32, 82, 97, 162, 257, 272, 337, 512, 626, 641, 706, 881, 1250, 1297, 1312, 1377, 1552, 1921, 2402, 2417, 2482, 2592, 2657, 3026, 3697, 4097, 4112, 4177, 4352, 4721, 4802, 5392, 6497, 6562, 6577, 6642, 6817, 7186, 7857, 8192, 8962, 10001, 10016, 10081, 10256, 10625, 10657, 11296, 12401, 13122, 14096, 14642 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Differs from A003336 at term 11660 because 635318657 = 59^4 + 158^4 = 133^4 + 134^4

LINKS

David Consiglio, Jr., Table of n, a(n) for n = 1..20000

EXAMPLE

32 is a member of this sequence because 32 = 2^4 + 2^4

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, 2):

    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

Cf. A003336, A338667, A344188.

Sequence in context: A078164 A060387 A003336 * A212740 A212742 A178145

Adjacent sequences:  A344184 A344185 A344186 * A344188 A344189 A344190

KEYWORD

nonn

AUTHOR

David Consiglio, Jr., May 11 2021

STATUS

approved

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Last modified September 19 16:34 EDT 2021. Contains 347564 sequences. (Running on oeis4.)