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%I #18 Oct 13 2017 05:50:20
%S 2741256,4118877,6017193,6742008,9016488,16776487,21930048,28699272,
%T 32951016,36875384,42549416,48137544,48275136,52324993,53936064,
%U 70957971,72131904,74013912,87539319,94287375,102977784,105651000,111209679,119824488,122262264,124454421,134211896
%N Sum of two (possibly negative) cubes in at least 4 ways.
%C This sequence is infinite, since if n is in the sequence so is n*k^3 for all k > 0; thus a(n) << n^3. - _Charles R Greathouse IV_, Nov 29 2014
%H Rosalie Fay, <a href="/A051384/b051384.txt">Table of n, a(n) for n = 1..100</a>
%H Joseph H. Silverman, <a href="http://www.maa.org/programs/maa-awards/writing-awards/taxicabs-and-sums-of-two-cubes">Taxicabs and sums of two cubes</a>, Amer. Math. Monthly, 100 (1993), 331-340.
%e 42549416 = 348^3+74^3 = 282^3+272^3 = (-2662)^3+2664^3 = (-475)^3+531^3, so 42549416 is in the sequence. (Silverman)
%o (PARI) T=thueinit('z^3+1);is(n)=my(v=thue(T, n)); #v>6 && #select(u->u[1]<=u[2],v)>3 \\ _Charles R Greathouse IV_, Nov 29 2014
%Y Cf. A051347, A051383.
%K nonn
%O 1,1
%A _Colin Mallows_
%E a(6)-a(22) from _Donovan Johnson_, Apr 17 2010
%E Missing terms 42549416, 48275136, 94287375, 111209679, 124454421 added by _Rosalie Fay_, Oct 13 2017
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