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Decimal expansion of cosh(EulerGamma).
+10
5
1, 1, 7, 1, 2, 6, 5, 9, 5, 0, 7, 7, 8, 5, 4, 1, 5, 7, 7, 5, 3, 0, 3, 2, 3, 6, 5, 8, 9, 4, 9, 0, 3, 0, 1, 6, 7, 9, 6, 7, 6, 7, 7, 8, 0, 0, 6, 1, 4, 2, 9, 1, 6, 8, 6, 7, 5, 5, 9, 1, 2, 4, 7, 6, 2, 7, 8, 9, 6, 4, 5, 2, 1, 9, 4, 3, 9, 3, 6, 9, 6, 5, 4, 2, 0, 2, 2, 2, 6, 8, 7, 7, 1, 1, 3, 1, 6, 3, 1, 9
OFFSET
1,3
LINKS
EXAMPLE
1.171265950778541577530323658949030167967677800614291686755912...
MATHEMATICA
First[RealDigits[N[(Exp[EulerGamma] + Exp[ -EulerGamma])/2, 100]]]
PROG
(PARI) default(realprecision, 100); cosh(Euler) \\ G. C. Greubel, Aug 29 2018
(Magma) SetDefaultRealField(RealField(100)); R:= RealField(); Cosh(EulerGamma(R)); // G. C. Greubel, Aug 29 2018
CROSSREFS
Cf. A147709 (with sinh), A147710 (with tanh), A147711 (with coth).
KEYWORD
cons,nonn
AUTHOR
Artur Jasinski, Nov 11 2008
STATUS
approved
Decimal expansion of sinh(EulerGamma).
+10
5
6, 0, 9, 8, 0, 6, 4, 6, 7, 2, 1, 1, 6, 5, 6, 4, 0, 7, 7, 0, 6, 1, 8, 0, 4, 4, 4, 1, 5, 8, 1, 4, 9, 3, 8, 1, 2, 0, 1, 9, 6, 7, 4, 1, 3, 6, 8, 9, 1, 3, 8, 5, 1, 8, 6, 0, 1, 7, 5, 3, 4, 0, 0, 2, 3, 3, 8, 7, 6, 5, 5, 4, 8, 6, 9, 6, 5, 1, 3, 2, 8, 2, 8, 7, 3, 5, 1, 5, 2, 8, 7, 7, 7, 1, 0, 1, 9, 6, 0, 7
OFFSET
0,1
LINKS
EXAMPLE
Equals 0.6098064672116564077061804441581493812019674136891385186017534...
MATHEMATICA
First[RealDigits[N[(Exp[EulerGamma] - Exp[ -EulerGamma])/2, 100]]]
RealDigits[Sinh[EulerGamma], 10, 120][[1]] (* Harvey P. Dale, Mar 06 2013 *)
PROG
(PARI) default(realprecision, 100); (exp(Euler) - exp(-Euler))/2 \\ G. C. Greubel, Aug 29 2018
(Magma) SetDefaultRealField(RealField(100)); R:= RealField(); (Exp(EulerGamma(R)) - Exp(-EulerGamma(R)))/2; // G. C. Greubel, Aug 29 2018
CROSSREFS
Cf. A147708 (with cosh), A147710 (with tanh), A147711 (with coth).
KEYWORD
cons,nonn
AUTHOR
Artur Jasinski, Nov 11 2008
EXTENSIONS
Leading zero removed, offset adjusted by R. J. Mathar, Feb 05 2009
Corrected by Harvey P. Dale, Mar 06 2013
STATUS
approved
Decimal expansion of tanh(EulerGamma).
+10
4
5, 2, 0, 6, 3, 8, 7, 7, 2, 7, 7, 9, 4, 1, 6, 5, 5, 8, 8, 2, 9, 3, 9, 4, 5, 9, 1, 6, 6, 9, 0, 2, 8, 1, 3, 4, 2, 8, 7, 6, 7, 3, 1, 9, 3, 8, 1, 0, 4, 8, 7, 6, 0, 8, 2, 6, 5, 4, 0, 3, 6, 9, 0, 1, 6, 8, 5, 5, 7, 2, 6, 4, 6, 1, 3, 1, 8, 9, 4, 4, 6, 1, 0, 4, 2, 5, 7, 5, 2, 9, 2, 0, 7, 1, 7, 1, 2, 7, 6, 4
OFFSET
0,1
LINKS
EXAMPLE
0.52063877277941655882939459166902813428767319381048760826540...
MATHEMATICA
First[RealDigits[N[(Exp[EulerGamma] - Exp[ -EulerGamma])/(Exp[EulerGamma] + Exp[ -EulerGamma]), 100]]]
RealDigits[Tanh[EulerGamma], 10, 120][[1]] (* Harvey P. Dale, Aug 10 2020 *)
PROG
(PARI) default(realprecision, 100); tanh(Euler) \\ G. C. Greubel, Aug 29 2018
(Magma) SetDefaultRealField(RealField(100)); R:= RealField(); Tanh(EulerGamma(R)); // G. C. Greubel, Aug 29 2018
CROSSREFS
Cf. A147708 (with cosh), A147709 (with sinh), A147711 (with coth).
KEYWORD
cons,nonn
AUTHOR
Artur Jasinski, Nov 11 2008
EXTENSIONS
Leading zero removed and offset adjusted by R. J. Mathar, Feb 05 2009
STATUS
approved
Decimal expansion of coth(EulerGamma).
+10
4
1, 9, 2, 0, 7, 1, 7, 4, 9, 6, 0, 5, 1, 1, 0, 2, 7, 3, 7, 9, 7, 3, 6, 4, 8, 6, 6, 3, 4, 8, 3, 2, 1, 1, 2, 5, 5, 4, 7, 9, 1, 0, 6, 1, 9, 4, 0, 2, 4, 9, 7, 6, 1, 5, 5, 4, 4, 1, 2, 6, 4, 9, 1, 8, 9, 0, 1, 9, 9, 7, 8, 5, 5, 8, 7, 1, 2, 2, 5, 2, 1, 0, 5, 2, 1, 7, 0, 8, 1, 1, 9, 0, 9, 9, 6, 2, 1, 1, 5, 7
OFFSET
1,2
LINKS
EXAMPLE
1.920717496051102737973648663483211255479106194024976155441...
MATHEMATICA
First[RealDigits[N[(Exp[EulerGamma] + Exp[ -EulerGamma])/(Exp[EulerGamma] - Exp[ -EulerGamma]), 100]]]
PROG
(PARI) default(realprecision, 100); (exp(Euler) + exp(-Euler))/(exp(Euler) - exp(-Euler)) \\ G. C. Greubel, Aug 29 2018
(PARI) 1/tanh(Euler) \\ Charles R Greathouse IV, May 14 2019
(Magma) SetDefaultRealField(RealField(100)); R:= RealField(); (Exp(EulerGamma(R)) + Exp(-EulerGamma(R)))/(Exp(EulerGamma(R)) - Exp(-EulerGamma(R))); // G. C. Greubel, Aug 29 2018
CROSSREFS
Cf. A147708 (with cosh), A147709 (with sinh), A147710 (with tanh).
KEYWORD
cons,nonn
AUTHOR
Artur Jasinski, Nov 11 2008
STATUS
approved
Beatty sequence for 1 + 1/gamma^2.
+10
3
4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 52, 56, 60, 64, 68, 72, 76, 80, 84, 88, 92, 96, 100, 104, 108, 112, 116, 120, 124, 128, 132, 136, 140, 144, 148, 152, 156, 160, 164, 168, 172, 176, 180, 184, 188, 192, 196, 200, 204, 208, 212, 216, 220, 224, 228
OFFSET
1,1
COMMENTS
The first term where this sequence breaks the progression a(n) = a(n-1) + 4 is a(715) = 2861. - Max Alekseyev, Mar 03 2007
LINKS
Aviezri S. Fraenkel, Jonathan Levitt, Michael Shimshoni, Characterization of the set of values f(n)=[n alpha], n=1,2,..., Discrete Math. 2 (1972), no.4, 335-345.
Tanya Khovanova, Non Recursions
Eric Weisstein's World of Mathematics, Beatty Sequence.
FORMULA
a(n) = floor(n*(1+1/gamma^2)) where 1+1/gamma^2= 1+A098907^2 = 4.00139933... - R. J. Mathar, Sep 29 2023
MATHEMATICA
Floor[Range[100]*(1 + 1/EulerGamma^2)] (* Paolo Xausa, Jul 05 2024 *)
PROG
(PARI) { default(realprecision, 100); b=1 + 1/Euler^2; for (n = 1, 2000, write("b059558.txt", n, " ", floor(n*b)); ) } \\ Harry J. Smith, Jun 28 2009
CROSSREFS
Beatty complement is A059557.
KEYWORD
nonn,easy
AUTHOR
Mitch Harris, Jan 22 2001
EXTENSIONS
Removed incorrect comment, Joerg Arndt, Nov 14 2014
STATUS
approved
Engel expansion of 1/gamma, (gamma is the Euler-Mascheroni constant A001620) = 1.73245.
+10
1
1, 2, 3, 3, 6, 10, 20, 46, 226, 1836, 3719, 14308, 17262, 129530, 945152, 1535786, 2229882, 3560447, 9434930, 20957352, 102311436, 312567415, 449243761, 4362956254, 12000988888, 22909186976, 29969826721
OFFSET
1,2
COMMENTS
Cf. A006784 for definition of Engel expansion.
REFERENCES
F. Engel, Entwicklung der Zahlen nach Stammbruechen, Verhandlungen der 52. Versammlung deutscher Philologen und Schulmaenner in Marburg, 1913, pp. 190-191.
LINKS
G. C. Greubel and T. D. Noe, Table of n, a(n) for n = 1..1000[Terms 1 to 300 computed by T. D. Noe; Terms 301 to 1000 computed by G. C. Greubel, Dec 27 2016]
F. Engel, Entwicklung der Zahlen nach Stammbruechen, Verhandlungen der 52. Versammlung deutscher Philologen und Schulmaenner in Marburg, 1913, pp. 190-191. English translation by Georg Fischer, included with his permission.
P. Erdős and Jeffrey Shallit, New bounds on the length of finite Pierce and Engel series, Sem. Theor. Nombres Bordeaux (2) 3 (1991), no. 1, 43-53.
MATHEMATICA
EngelExp[A_, n_] := Join[Array[1 &, Floor[A]], First@Transpose@
NestList[{Ceiling[1/Expand[#[[1]] #[[2]] - 1]], Expand[#[[1]] #[[2]] - 1]/1} &, {Ceiling[1/(A - Floor[A])], (A - Floor[A])/1}, n - 1]];
EngelExp[N[EulerGamma^2, 7!], 100] (* Modified by G. C. Greubel, Dec 27 2016 *)
CROSSREFS
Cf. A098907.
KEYWORD
nonn,easy,nice
AUTHOR
STATUS
approved
a(n) = the smallest prime > (1/EulerGamma)^n.
+10
0
2, 5, 7, 11, 17, 29, 47, 83, 149, 251, 431, 733, 1277, 2203, 3803, 6599, 11411, 19777, 34253, 59333, 102793, 178067, 308489, 534431, 925891, 1604021, 2778901, 4814321, 8340593, 14449651, 25033357, 43369111, 75135077, 130168021, 225510203
OFFSET
1,1
COMMENTS
EulerGamma is Euler's constant (or the Euler-Mascheroni constant) gamma (A001620).
1/EulerGamma = 1.7324547146006... (A098907).
EXAMPLE
The first prime > (1/EulerGamma)^6 = 27.03779975... is 29, so a(6) = 29.
MATHEMATICA
Table[Prime[PrimePi[1/EulerGamma^n] + 1], {n, 1, 40}]
NextPrime/@Table[1/EulerGamma^n, {n, 40}] (* Harvey P. Dale, May 10 2020 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Michel Lagneau, Nov 21 2010
STATUS
approved
Primes found in decimal expansion of 1/EulerGamma.
+10
0
17, 173, 173245471460063, 1732454714600633
OFFSET
1,1
COMMENTS
Primes found in A098907.
EXAMPLE
1/EulerGamma =1.732454714600633473583... so a(1)=17 ; a(2) =173,...
MAPLE
Digits := 100; n0 := evalf(1/gamma); for i from 1 to 500 do x := trunc(10^i*n0):
if isprime(x) then printf(`%d, `, x): fi: od:
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Michel Lagneau, Nov 24 2010
STATUS
approved
Decimal expansion of gamma^(1/gamma), where gamma is the Euler-Mascheroni constant.
+10
0
3, 8, 5, 9, 4, 8, 2, 5, 4, 7, 1, 9, 8, 4, 1, 0, 5, 8, 0, 3, 7, 3, 6, 5, 0, 0, 8, 1, 1, 7, 5, 3, 7, 2, 0, 8, 4, 5, 3, 5, 7, 1, 5, 6, 2, 5, 0, 1, 4, 0, 5, 9, 6, 5, 4, 6, 7, 6, 9, 4, 0, 5, 4, 1, 8, 1, 9, 6, 6, 5, 7, 5, 1, 5, 6, 3, 4, 3, 2, 0, 8, 8, 5, 2, 9, 2, 3, 5, 9, 9
OFFSET
0,1
EXAMPLE
0.385948254719841058037365008117537208453571562501405965467694054181966575...
MAPLE
Digits := 100; evalf(gamma^(1/gamma));
MATHEMATICA
RealDigits[EulerGamme^(1/EulerGamma), 10, 100][[1]]
PROG
(PARI) Euler^(1/Euler)
KEYWORD
nonn,cons
AUTHOR
Christoph B. Kassir, Aug 30 2021
STATUS
approved

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