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%I #4 Oct 17 2014 23:19:43
%S 2,4,7,8,10,12,14,15,17,19,20,22,23,25,26,28,29,31,32,34,35,37,38,40,
%T 41,43,44,46,47,48,50,51,53,54,56,57,59,60,61,63,64,66,67,69,70,71,73,
%U 74,76,77,78,80,81,83,84,86,87,88,90,91,93,94,95,97,98
%N Numbers k such that A248636(k+1) = A248636(k) + 1.
%H Clark Kimberling, <a href="/A248637/b248637.txt">Table of n, a(n) for n = 1..1000</a>
%e (A248636(k+1) = A248636(k)) = (2, 1, 2, 1, 2, 2, 1, 1, 2, 1, 2, 1, 2, 1, 1, 2,... ), so that A248637 = (2, 4, 7, 8, 10, 12, 14, ... ) and A248638 = (1, 3, 5, 6, 9, 11, 13, ...).
%t z = 300; p[k_] := p[k] = Sum[(h^3/3^h), {h, 1, k}];
%t d = N[Table[33/8 - p[k], {k, 1, z/5}], 12]
%t f[n_] := f[n] = Select[Range[z], 33/8 - p[#] < 1/4^n &, 1];
%t u = Flatten[Table[f[n], {n, 1, z}]] (* A248636 *)
%t d = Differences[u]
%t v = Flatten[Position[d, 1]] (* A248637 *)
%t w = Flatten[Position[d, 2]] (* A248638 *)
%Y Cf. A248635, A248636, A248630.
%K nonn,easy
%O 1,1
%A _Clark Kimberling_, Oct 11 2014