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 A018850 Numbers that are the sum of 2 cubes in more than 1 way (primitive solutions). 4
 1729, 4104, 20683, 39312, 40033, 64232, 65728, 134379, 149389, 171288, 195841, 216027, 327763, 402597, 439101, 443889, 515375, 684019, 704977, 805688, 842751, 920673, 955016, 984067, 994688, 1009736, 1016496, 1073375, 1092728, 1331064 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Nakao's table has more entries because he lists nonprimitive numbers if they are the sum of two cubes in three ways. Rajesh Bhowmick, Dec 12 2011: The odd number 40533595075161 can be represented as sum of two cubes in just two different ways: (34314)^(3)+(5073)^(3) = (34321)^(3)+(4730)^(3). Here, the cubes are greater than 1, there is no common factor between the odd numbers, there is no common factor between the L.H.S & the R.H.S, the even number is greater than 2, the cubes are in their primitive form, and they are not of the form (27)^(3) or (121)^(3) (which are actually (3)^(9) & (11)^(6)). LINKS Shahar Amitai, Table of n, a(n) for n = 1..9859 (terms a(1)-a(1694) from T. D. Noe). H. Nakao, Ramanujan Taxi Numbers [1...1000000000] Eric Weisstein's World of Mathematics, Cubic Number CROSSREFS Cf. A001235. Sequence in context: A242880 A001235 A343708 * A062924 A130859 A245671 Adjacent sequences:  A018847 A018848 A018849 * A018851 A018852 A018853 KEYWORD nonn AUTHOR STATUS approved

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Last modified May 14 06:35 EDT 2021. Contains 343879 sequences. (Running on oeis4.)