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A339990
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Sums of two odd cubes.
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3
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2, 28, 54, 126, 152, 250, 344, 370, 468, 686, 730, 756, 854, 1072, 1332, 1358, 1456, 1458, 1674, 2060, 2198, 2224, 2322, 2540, 2662, 2926, 3376, 3402, 3500, 3528, 3718, 4104, 4394, 4706, 4914, 4940, 5038, 5256, 5572, 5642, 6244, 6750, 6860, 6886, 6984, 7110, 7202
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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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28 is in the sequence since 1^3 + 3^3 = 1 + 27 = 28, with 1 and 27 both odd.
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MATHEMATICA
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Table[If[Sum[Mod[i, 2] Mod[n - i, 2] (Floor[i^(1/3)] - Floor[(i - 1)^(1/3)]) (Floor[(n - i)^(1/3)] - Floor[(n - i - 1)^(1/3)]), {i, Floor[n/2]}] > 0, n, {}], {n, 1200}] // Flatten
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PROG
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(Python)
def aupto(lim):
ocs = [k**3 for k in range(1, int(lim**(1/3)+2), 2)]
return sorted(set(c1+c2 for c1 in ocs for c2 in ocs if c1+c2 <= lim))
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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