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%I #19 Oct 12 2017 10:53:15
%S 1,1,2,3,4,5,1,2,3,4,5,6,2,3,4,1,2,3,3,4,5,2,3,4,4,5,6,3,4,1,2,3,4,4,
%T 5,2,3,4,5,5,6,3,4,5,2,3,4,4,5,1,2,3,4,5,6,2,3,4,2,3,4,3,4,5,2,3,4,4,
%U 5,6,3,4,5,3,4,5,1,2,2,3,4,5,2,3,3,4,5,3,3,4,4,2,3,3,4,5,5,3,2,3,4,5,4,4,3,2,3,3,4,5,4,1,2,3,4,5,4,2,3,4,3
%N Minimal number of terms of A005826 needed to sum to n.
%C Watson showed that a(n) <= 8 for all n.
%C It is likely that a(n) <= 6 for all n (see A193107).
%H H. E. Salzer and N. Levine, <a href="https://doi.org/10.1090/S0025-5718-1968-0224578-6">Proof that every integer <= 452,479,659 is a sum of five numbers of the form Q_x = (x^3+5x)/6, x>= 0</a>, Math. Comp., (1968), 191-192.
%H G. L. Watson, <a href="https://doi.org/10.1112/jlms/s1-27.2.217">Sums of eight values of a cubic polynomial</a>, J. London Math. Soc., 27 (1952), 217-224.
%p t1:=[seq((n^3-7*n)/6, n=3..20)];
%p LAGRANGE(t1, 8 120); # the LAGRANGE transform of a sequence is defined in A193101 - _N. J. A. Sloane_, Jul 15 2011
%Y Cf. A005826, A193107.
%K nonn
%O 1,3
%A _N. J. A. Sloane_, Jul 15 2011
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