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%I #18 Dec 15 2017 17:35:15
%S -3,-2,0,0,4,2,6,6,10,7,15,9,18,18,21,15,28,18,31,29,34,24,41,32,42,
%T 39,48,34,57,38,54,53,60,55,69,48,69,66,76,55,86,59,84,83,87,66,99,76,
%U 101,92,103,78,115,95,114,105,116,89,134,93,126,123,130,117,148,105,142,133
%N a(n) = floor(exp(gamma) n log log n ) - phi(n), where gamma is Euler's constant (A001620).
%H Harry J. Smith, <a href="/A062787/b062787.txt">Table of n, a(n) for n = 2..1000</a>
%t Table[Floor[N[Exp[EulerGamma] * n * Log[Log[n]] - EulerPhi[n], 20]], {n, 2, 70}] (* _G. C. Greubel_, Dec 31 2016 *)
%o (PARI) for(n=2,24,print(floor(exp(Euler)*n*log(log(n)))-eulerphi(n)))
%o (PARI) { default(realprecision, 50); c=exp(Euler); for (n=2, 1000, write("b062787.txt", n, " ", c*n*log(log(n))\1 - eulerphi(n)) ) } \\ _Harry J. Smith_, Aug 11 2009
%Y Cf. A058209.
%K easy,sign
%O 2,1
%A _Jason Earls_, Jul 18 2001
%E More terms added by _Harry J. Smith_, Aug 11 2009