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A337657 Let M_k denote the addition table for the first k terms of A337656. M_k contains exactly k*(k+1)/2 distinct numbers, and these numbers are a subset of the entries in M_{k+1}. The present sequence consists of the numbers that never appear in any M_k.

%I A337657 #22 Oct 08 2020 03:31:48
%S A337657 5,9,11,16,17,18,22,25,26,28,29,34,35,36,38,39,41,43,46,48,49,52,53,
%T A337657 54,55,57,58,59,61,62,63,67,69,70,71,73,75,76,78,79,80,81,82,83,84,86,
%U A337657 87,89,90,93,96,97,99,100,101,102,104,105,106,112,113,115,116,117,118,120,124,126,128
%N A337657 Let M_k denote the addition table for the first k terms of A337656. M_k contains exactly k*(k+1)/2 distinct numbers, and these numbers are a subset of the entries in M_{k+1}. The present sequence consists of the numbers that never appear in any M_k.
%C A337657 Note that if A337656(k+1) = t, all entries in M_{k+1} that are not entries in M_k are >= t.
%H A337657 Rémy Sigrist, <a href="/A337657/b337657.txt">Table of n, a(n) for n = 1..10000</a>
%H A337657 Rémy Sigrist, <a href="/A337657/a337657.txt">C++ program for A337657</a>
%e A337657 The addition table, M_9:
%e A337657    + |  0  1  3  7 12 20 30  44  65
%e A337657 -----+-----------------------------
%e A337657    0 |  0
%e A337657    1 |  1  2
%e A337657    3 |  3  4  6
%e A337657    7 |  7  8 10 14
%e A337657   12 | 12 13 15 19 24
%e A337657   20 | 20 21 23 27 32 40
%e A337657   30 | 30 31 33 37 42 50 60
%e A337657   44 | 44 45 47 51 56 64 74  88
%e A337657   65 | 65 66 68 72 77 85 95 109 130
%o A337657 (C++) See Links section.
%Y A337657 Cf. A337655, A337656, A337658.
%K A337657 nonn
%O A337657 1,1
%A A337657 _N. J. A. Sloane_, Oct 01 2020