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Greatest number m such that the fractional part of (10/9)^A153696(n) >= 1-(1/m).
+20
4
1, 8, 15, 264, 8741, 15912, 409895
OFFSET
1,2
FORMULA
a(n):=floor(1/(1-fract((10/9)^A153696(n)))), where fract(x) = x-floor(x).
EXAMPLE
a(3)=15, since 1-(1/16)=0.9375>fract((10/9)^A153696(3))=fract((10/9)^13)=0.9341...>=1-(1/15).
KEYWORD
nonn,more
AUTHOR
Hieronymus Fischer, Jan 06 2009
STATUS
approved
Numbers k such that the fractional part of (101/100)^k is greater than 1-(1/k).
+10
14
1, 69, 180, 783, 859, 1803, 10763, 19105, 39568, 50172, 132572, 355146, 1452050, 2245950, 3047334, 3933030, 4165171, 98544173
OFFSET
1,2
COMMENTS
Numbers k such that fract((101/100)^k) > 1-(1/k), where fract(x) = x-floor(x).
The next term is greater than 2*10^8.
EXAMPLE
a(2) = 69, since fract((101/100)^69) = 0.9868... > 0.9855... = 1 - (1/69), but fract((101/100)^k) <= 1 - (1/k) for 1 < k < 69.
MATHEMATICA
Select[Range[1000], FractionalPart[(101/100)^#] >= 1 - (1/#) &] (* G. C. Greubel, Aug 24 2016 *)
KEYWORD
nonn,more
AUTHOR
Hieronymus Fischer, Jan 06 2009
EXTENSIONS
a(13)-a(18) from Robert Gerbicz, Nov 22 2010
STATUS
approved
Numbers k such that the fractional part of (1024/1000)^k is greater than 1-(1/k).
+10
11
1, 29, 82, 134, 277, 1306, 2036, 2349, 6393, 9389, 9816, 21689, 34477, 145984, 171954, 956357, 2746739
OFFSET
1,2
COMMENTS
Numbers k such that fract((1024/1000)^k) > 1-(1/k), where fract(x) = x-floor(x).
The next such number must be greater than 5*10^5.
EXAMPLE
a(2) = 29, since fract((1024/1000)^29) = 0.98929... > 0.9655... = 1 - (1/29), but fract((1024/1000)^k) <= 1 - (1/k) for 1 < k < 29.
MATHEMATICA
Select[Range[1000], FractionalPart[(1024/1000)^#] >= 1 - (1/#) &] (* G. C. Greubel, Aug 24 2016 *)
KEYWORD
nonn,more
AUTHOR
Hieronymus Fischer, Jan 06 2009
EXTENSIONS
a(16)-a(17) from Hagen von Eitzen, May 16 2009
STATUS
approved
Numbers k such that the fractional part of (11/10)^k is greater than 1-(1/k).
+10
11
1, 7, 77, 103, 320, 1821, 2992, 15290, 88651, 88652, 180168, 410498, 548816, 672732
OFFSET
1,2
COMMENTS
Numbers k such that fract((11/10)^k) > 1-(1/k), where fract(x) = x-floor(x).
The next such number must be greater than 2*10^5.
a(15) > 10^7. Robert Price, Mar 19 2019
EXAMPLE
a(2) = 7, since fract((11/10)^7) = 0.9487... > 0.8571... = 1 - (1/7), but fract((11/10)^k) <= 1 - (1/k) for 1 < k < 7.
MATHEMATICA
Select[Range[1000], FractionalPart[(11/10)^#] >= 1 - (1/#) &] (* G. C. Greubel, Aug 24 2016 *)
KEYWORD
nonn,more
AUTHOR
Hieronymus Fischer, Jan 06 2009
EXTENSIONS
a(12)-a(14) from Robert Price, Mar 19 2019
STATUS
approved
Numbers k such that the fractional part of e^k is greater than 1-(1/k).
+10
10
1, 8, 19, 178, 209, 1907, 32653, 119136, 220010
OFFSET
1,2
COMMENTS
Numbers k such that fract(e^k) > 1-(1/k), where fract(x) = x-floor(x).
The next such number must be greater than 100000.
a(10) > 300,000. Robert Price, Mar 23 2019
EXAMPLE
a(2)=8, since fract(e^8) = 0.957987... >0.875 = 1-(1/8), but fract(e^k) = 0.389..., 0.085..., 0.598..., 0.413..., 0.428..., 0.633... for 2<=k<=7 which all are less than 1-(1/k).
MATHEMATICA
Select[Range[2000], N[FractionalPart[E^#], 1000] >= 1 - (1/#) &] (* G. C. Greubel, Aug 25 2016 *)
KEYWORD
nonn,more
AUTHOR
Hieronymus Fischer, Jan 06 2009
EXTENSIONS
a(8)-a(9) from Robert Price, Mar 23 2019
STATUS
approved
Numbers k such that the fractional part of Pi^k is greater than 1-(1/k).
+10
9
1, 2, 15, 22, 58, 109, 157, 1030, 1071, 1274, 2008, 2322, 5269, 151710
OFFSET
1,2
COMMENTS
Numbers k such that fract(Pi^k) > 1-(1/k), where fract(x) = x-floor(x).
The next such number must be greater than 100000.
a(15) > 300000. - Robert Price, Mar 25 2019
EXAMPLE
a(3) = 15, since fract(Pi^15) = 0.969... > 0.933... = 1 - (1/15), but fract(Pi^k) <= 1 - (1/k) for 3 <= k <= 14.
MATHEMATICA
Select[Range[1000], N[FractionalPart[Pi^#], 100] > 1 - (1/#) &] (* G. C. Greubel, Aug 25 2016 *)
KEYWORD
nonn,more
AUTHOR
Hieronymus Fischer, Jan 06 2009
EXTENSIONS
a(14) from Robert Price, Mar 25 2019
STATUS
approved
Greatest number m such that the fractional part of e^A153704(n) >= 1-(1/m).
+10
7
3, 23, 27, 261, 348, 2720, 72944, 347065, 244543
OFFSET
1,1
FORMULA
a(n) = floor(1/(1-fract(e^A153704(n)))), where fract(x) = x-floor(x).
EXAMPLE
a(2) = 23, since 1-(1/24) = 0.9583... > fract(e^A153704(2)) = fract(e^8) = 0.95798... >= 0.95652... >= 1-(1/23).
MATHEMATICA
A153704 = {1, 8, 19, 178, 209, 1907, 32653, 119136, 220010};
Table[fp = FractionalPart[E^A153704[[n]]]; m = Floor[1/fp];
While[fp >= 1 - (1/m), m++]; m - 1, {n, 1, Length[A153704]}] (* Robert Price, May 10 2019 *)
KEYWORD
nonn,more
AUTHOR
Hieronymus Fischer, Jan 06 2009
EXTENSIONS
a(8)-a(9) from Robert Price, May 10 2019
STATUS
approved
Greatest number m such that the fractional part of Pi^A153712(n) >= 1-(1/m).
+10
7
1, 7, 32, 53, 189, 131, 2665, 10810, 2693, 1976, 3697, 4289, 26577, 483367
OFFSET
1,2
FORMULA
a(n) = floor(1/(1-fract(Pi^A153712(n)))), where fract(x) = x-floor(x).
EXAMPLE
a(3) = 32, since 1-(1/33) = 0.9696... > fract(Pi^A153712(3)) = fract(Pi^15) = 0.96938... >= 0.96875 = 1-(1/32).
MATHEMATICA
A153712 = {1, 2, 15, 22, 58, 109, 157, 1030, 1071, 1274, 2008, 2322,
5269, 151710};
Table[Floor[1/(1 - FractionalPart[Pi^A153712[[n]]])], {n, 1,
Length[A153712]}] (* Robert Price, May 10 2019 *)
KEYWORD
nonn,more
AUTHOR
Hieronymus Fischer, Jan 06 2009
EXTENSIONS
a(14) from Robert Price, May 10 2019
STATUS
approved
Numbers k such that the fractional part of (Pi-2)^k is greater than 1-(1/k).
+10
7
1, 5, 8, 85, 911, 2921, 4491, 11543, 15724, 27683, 29921, 37276, 126659
OFFSET
1,2
COMMENTS
Numbers k such that fract((Pi-2)^k) > 1-(1/k), where fract(x) = x-floor(x).
The next such number must be greater than 200000.
a(14) > 300000. - Robert Price, Mar 26 2019
EXAMPLE
a(3) = 8, since fract((Pi-2)^8) = 0.8846247315... > 0.875 = 1 - (1/8), but fract((Pi-2)^k) = 0.2134..., 0.5268... <= 1 - (1/k) for 6 <= k <= 7.
MATHEMATICA
Select[Range[1000], N[FractionalPart[(Pi - 2)^#], 100] > 1 - (1/#) &] (* G. C. Greubel, Aug 25 2016 *)
KEYWORD
nonn,more
AUTHOR
Hieronymus Fischer, Jan 06 2009
STATUS
approved
Greatest number m such that the fractional part of (Pi-2)^A153720(n) >= 1-(1/m).
+10
7
1, 16, 8, 158, 946, 8786, 16159, 20188, 61392, 34039, 31425, 59154, 217556
OFFSET
1,2
FORMULA
a(n):=floor(1/(1-fract((Pi-2)^A153720(n)))), where fract(x) = x-floor(x).
EXAMPLE
a(4)=158, since 1-(1/159) = 0.993710... > fract((Pi-2)^A153720(4)) = fract(Pi^85) = 0.993693... >= 0.993670... = 1-(1/158).
MATHEMATICA
A153720 = {1, 5, 8, 85, 911, 2921, 4491, 11543, 15724, 27683, 29921,
37276, 126659};
Table[Floor[1/(1 - FractionalPart[(Pi - 2)^A153720[[n]]])], {n, 1,
Length[A153720]}] (* Robert Price, May 10 2019 *)
KEYWORD
nonn,more
AUTHOR
Hieronymus Fischer, Jan 06 2009
STATUS
approved

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