%I M1035 #13 Nov 07 2017 18:20:36
%S 1,2,4,7,10,12,16,17,32,36,42,57,72,73,98,102,104,129,159,164,174,189,
%T 199,221,224,255,286,287,347,372,378,403,428,443,444,469,494,529,560,
%U 586
%N Next term is uniquely the sum of 3 earlier terms.
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%D M. C. Wunderlich, The improbable behavior of Ulam's summation sequence, pp. 249-257 of A. O. L. Atkin and B. J. Birch, editors, Computers in Number Theory. Academic Press, NY, 1971.
%H R. G. Wilson, V, <a href="/A002858/a002858_3.pdf">Letter to N. J. A. Sloane, Sep. 1992</a>
%K nonn
%O 1,2
%A _N. J. A. Sloane_, _Robert G. Wilson v_