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%I #9 Apr 25 2024 19:22:43
%S 0,1,1,2,3,3,0,11,0,24,37,47,73,90,133,135,110,133,435,795,317,1674,
%T 1217,1975,4816,6177,9483,11885,17724,19562,22958,39870,48417,85452,
%U 114676,210482,133092,194048,524165,451743,1145779,1292884,1604772,2859433,4032594
%N a(n) is the difference between A084321(n) and the (n-1)th power of 2.
%C A084321 is the least number k such that between k! and (k+1)! there are n powers of 2.
%H Kevin Ryde, <a href="/A085355/b085355.txt">Table of n, a(n) for n = 1..1000</a>
%t LogBase2Stirling[n_] := Floor[ Log[2, 2 Pi n]/2 + n*Log[2, n/E] + Log[2, 1 + 1/(12n) + 1/(288n^2) - 139/(51840n^3) - 571/(2488320n^4) + 163879/(209018880n^5)]]; Do[k = 2^(n - 1); While[ LogBase2Stirling[k + 1] - LogBase2Stirling[k] < n, k++ ]; a[n] = k, {n, 1, 45}]; Table[ a[n] - 2^(n - 1), {n, 1, 45}]
%Y Cf. A084321.
%K nonn
%O 1,4
%A _Labos Elemer_ and _Robert G. Wilson v_, Jun 24 2003