A038847 Odd numbers that are differences between two positive cubes.

7, 19, 37, 61, 63, 91, 117, 127, 169, 189, 215, 217, 271, 279, 331, 335, 387, 397, 469, 485, 511, 513, 547, 631, 657, 665, 721, 817, 819, 875, 919, 973, 999, 1027, 1115, 1141, 1197, 1261, 1267, 1323, 1385, 1387, 1413, 1519, 1603, 1647, 1657, 1685, 1701

Offset

1,1

Links

Robert Israel, Table of n, a(n) for n = 1..10000

Maple

N:= 2000: # to get all terms <= N
S:= {}:
for x from 1 to floor(1/2 + sqrt(12*N-3)/6) do
  S:= S union {seq(x^3-y^3, y= x-1..max(1, ceil(surd(x^3-N, 3))), -2)}
od:
sort(convert(S, list)); # Robert Israel, Jan 21 2019

Mathematica

With[{nn=50}, Take[Select[Union[Abs[#[[2]]-#[[1]]]&/@Subsets[Range[nn]^3, {2}]], OddQ], nn]] (* Harvey P. Dale, Jan 18 2013 *)

Crossrefs

Cf. A038848.

Odd terms of A181123.

Sequence in context: A301717 A152540 A073859 * A130056 A136057 A177092

Adjacent sequences: A038844 A038845 A038846 * A038848 A038849 A038850

Keyword

nonn

Author

Jeff Burch

Extensions

Definition corrected by Robert Israel, Jan 21 2019

Status

approved