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A247779 Numbers k such that A247778(k+1) - A247778(k) = 1.

%I A247779 #4 Sep 25 2014 21:16:00
%S A247779 1,3,4,6,7,9,11,12,14,15,17,18,20,21,23,25,26,28,29,31,32,34,36,37,39,
%T A247779 40,42,43,45,46,48,50,51,53,54,56,57,59,60,62,64,65,67,68,70,71,73,75,
%U A247779 76,78,79,81,82,84,85,87,89,90,92,93,95,96,98,99,101,103
%N A247779 Numbers k such that A247778(k+1) - A247778(k) = 1.
%C A247779 Complement of A247780.
%H A247779 Clark Kimberling, <a href="/A247779/b247779.txt">Table of n, a(n) for n = 1..2000</a>
%e A247779 The values of e - (1 + 1/k)^k for k = 1..8 are approximately 0.718282, 0.468282, 0.347911, 0.276876, 0.229962, 0.196655, 0.171782, 0.152497, so that the first 6 terms of A247778 are 1,2,4,5,6,8, and the first three terms of A247779 are 1,3,4.
%t A247779 z = 600; f[n_] := f[n] = Select[Range[z], E - (1 + 1/#)^# < 1/n &, 1];
%t A247779 u = Flatten[Table[f[n], {n, 1, z}]]       (*A247778*)
%t A247779 d1 = Flatten[Position[Differences[u], 1]] (*A247779*)
%t A247779 d2 = Flatten[Position[Differences[u], 2]] (*A247780*)
%Y A247779 Cf. A247778, A247780.
%K A247779 nonn,easy
%O A247779 1,2
%A A247779 _Clark Kimberling_, Sep 23 2014