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A342832
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Sums of two distinct odd fourth powers.
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1
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82, 626, 706, 2402, 2482, 3026, 6562, 6642, 7186, 8962, 14642, 14722, 15266, 17042, 21202, 28562, 28642, 29186, 30962, 35122, 43202, 50626, 50706, 51250, 53026, 57186, 65266, 79186, 83522, 83602, 84146, 85922, 90082, 98162, 112082, 130322, 130402, 130946, 132722
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OFFSET
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1,1
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LINKS
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EXAMPLE
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82 is in the sequence since 82 = 1^4 + 3^4.
626 is in the sequence since 626 = 1^4 + 5^4.
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MATHEMATICA
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Quiet@Select[Range@60000, !Equal@@(a=First@PowersRepresentations[#, 2, 4])&&And@@OddQ@a&] (* Giorgos Kalogeropoulos, Apr 24 2021 *)
Union[Total/@Subsets[Range[1, 19, 2]^4, {2}]] (* Harvey P. Dale, Jan 24 2022 *)
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PROG
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(Python)
def aupto(limit):
ofps = [i**4 for i in range(1, int(limit**.25)+2, 2) if i**4 < limit]
ss = set(f+g for i, f in enumerate(ofps) for g in ofps[i+1:])
return sorted(s for s in ss if s <= limit)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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