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%I #19 Jan 03 2016 04:36:13
%S -1,0,6,17,18,22,25,37,43,58,59,67,74,103,148,149,163,164,177,205,223,
%T 226,232,267,268,326,359,386,522,566,630,638,652,719,790,792,928,940,
%U 986,1005,1014,1169,1194,1213,1245,1257,1293,1326,1332,1353,1441,1467
%N Values of n for which exp(Pi*sqrt(n)) is very close to an integer.
%C Very close is defined here as being less than 1/100.
%C e^(Pi*sqrt(163)) is 262537412640768743.9999999999992500725971981856888... and no closer exponent of this character has been discovered. See A069014.
%t Select[ Range[ -1, 1480], Abs[ Round[E^(Pi*Sqrt[ # ])] - E^(Pi*Sqrt[ # ])] < 0.01 &]
%o (Contribution from _M. F. Hasler_, Jan 26 2014) (Start)
%o /* Adjusting the p-value allows one to select more interesting subsequences. */
%o (PARI) is_A019296(n,p=2)=abs(frac(exp(sqrt(n)*Pi))-.5)>.5-.1^p
%o (PARI) {p=.5-.1^2; for(n=1,9e9,abs(frac(exp(sqrt(n)*Pi))-.5)>p&&print1(round(exp(sqrt(n)*Pi))",")) \\ (End)
%Y Cf. A003173, A019297, A035484, A069014.
%K sign
%O -1,3
%A Roy Williams Clickery (roy(AT)ccsf.caltech.edu)
%E Edited and extended by _Robert G. Wilson v_, Sep 07 2003
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