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Larger of the two Ulam numbers that sum to the n-th Ulam number.
4

%I #8 Mar 30 2012 18:34:55

%S 0,0,2,3,4,6,8,11,13,16,18,26,28,36,36,47,47,53,36,53,69,69,69,69,69,

%T 97,99,102,106,69,69,102,97,145,102,106,175,177,180,102,189,180,206,

%U 206,219,189,236,238,241,206,189,258,260,180,273,219,316,316,282,339

%N Larger of the two Ulam numbers that sum to the n-th Ulam number.

%C The first two are zero because the Ulam sequence (A002858) is initialized for those terms. The smaller term in the sum is in A080328 and the indices are in A080330 and A080331.

%H T. D. Noe, <a href="/A080329/b080329.txt">Table of n, a(n) for n=1..10000</a>

%e The 11th Ulam number (26) is the sum of the 6th Ulam number (8) and the 10th Ulam number (18), so a(11)=18.

%Y Cf. A002858, A080328, A080330, A080331.

%K nonn

%O 1,3

%A _Jud McCranie_, Feb 15 2003