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A228499 Sums of two rational cubes, excluding cubes and twice cubes. 0
6, 7, 9, 12, 13, 15, 17, 19, 20, 22, 26, 28, 30, 31, 33, 34, 35, 37, 42, 43, 48, 49, 50, 51, 53, 56, 58, 61, 62, 63, 65, 67, 68, 69, 70, 71, 72, 75, 78, 79, 84, 85, 86, 87, 89, 90, 91, 92, 94, 96, 97, 98, 103, 104, 105, 106, 107, 110, 114, 115, 117, 120, 123, 124 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Each term can be written as sum of two rational cubes infinitely many times.

REFERENCES

Wacław Sierpiński, Teoria liczb, cz. II, PWN, Warsaw, 1959, pp. 472-473.

LINKS

Table of n, a(n) for n=1..64.

Index entries for sequences related to sums of cubes

PROG

(PARI) for(n=1, 124, if(ellanalyticrank(ellinit([0, (4*n)^2]))[1]>0, print1(n, ", ")));

CROSSREFS

Cf. A020898. Subsequence of A159843.

Sequence in context: A095908 A094698 A096405 * A108595 A186079 A022938

Adjacent sequences:  A228496 A228497 A228498 * A228500 A228501 A228502

KEYWORD

nonn

AUTHOR

Arkadiusz Wesolowski, Aug 23 2013

STATUS

approved

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Last modified May 22 15:13 EDT 2019. Contains 323480 sequences. (Running on oeis4.)