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A078131 Numbers which can be written as sum of cubes > 1.

%I A078131 #24 Feb 16 2025 08:32:48
%S A078131 8,16,24,27,32,35,40,43,48,51,54,56,59,62,64,67,70,72,75,78,80,81,83,
%T A078131 86,88,89,91,94,96,97,99,102,104,105,107,108,110,112,113,115,116,118,
%U A078131 120,121,123,124,125,126,128,129,131,132,133,134,135,136,137,139,140
%N A078131 Numbers which can be written as sum of cubes > 1.
%C A078131 A078128(a(n)) > 0.
%H A078131 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/CubicNumber.html">Cubic Number</a>.
%H A078131 <a href="/index/Su#ssq">Index entries for sequences related to sums of cubes</a>
%F A078131 a(n) = n + 83 for n >= 72. - _Robert Israel_, Apr 05 2020
%e A078131 35 is in the sequence because 35 = 27 + 8.
%p A078131 a:=proc(n) local h, hser: h:=1/product(1-x^(j^3),j=2..30): hser:=series(h,x=0,150): if coeff(hser,x^n)>0 then n else fi end: seq(a(n),n=1..140); # _Emeric Deutsch_, Mar 30 2006
%t A078131 terms = 60;
%t A078131 (Exponent[#, x]& /@ List @@ Normal[1/Product[1-x^j^3, {j, 2, Ceiling[(3 terms)^(1/3)]}] + O[x]^(3 terms)])[[2 ;; terms+1]] (* _Jean-François Alcover_, Aug 04 2018, after _Emeric Deutsch_ *)
%Y A078131 Cf. A000578, A078129 (complement of this sequence), A078130, A078137.
%K A078131 nonn
%O A078131 1,1
%A A078131 _Reinhard Zumkeller_, Nov 19 2002