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A352223
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Second members D of two non-consecutive numbers such that the sums of their cubes are equal to centered cube numbers and to at least one other sum of two cubes, i.e., A = B^3 + (B+1)^3 = C^3 + D^3 = E^3 + F^3.
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18
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18, -5, 107, -125, 712, -1152, -1719, -865, -5370, -7870, 2518, -963, -29949, -20030, 111491, 87797, 261536, 2274319, -140357, -3938794, -139674130, -792131385
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OFFSET
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1,1
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COMMENTS
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Numbers D such that A = B^3 + (B+1)^3 = C^3 + D^3 = E^3 + F^3 with C <> (D +- 1), E <> (F +- 1), E > C > B, C > |D| and E > |F|, where A = A352220(n), B = A352221(n), C = A352222(n), D = a(n) (this sequence), E = A352224(n) and F = A352225(n).
Terms in Data are ordered according to increasing order of A352220(n) or A352221(n).
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LINKS
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A. Grinstein, Ramanujan and 1729, University of Melbourne Dept. of Math and Statistics Newsletter: Issue 3, 1998.
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FORMULA
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EXAMPLE
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18 belongs to the sequence as 153^3 + 18^3 = 121^3 + 122^3 = 369^3 + (-360)^3 = 3587409.
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CROSSREFS
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Cf. A005898, A001235, A272885, A352133, A352134, A352135, A352136, A352220, A352221, A352222, A352224, A352225.
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KEYWORD
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sign,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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