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Coefficients of the generalized continued fraction expansion sqrt(e) = a(1) +a(1)/(a(2) +a(2)/(a(3) +a(3)/(a(4) +a(4)/....))).
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%I #13 May 24 2014 01:55:47

%S 1,1,1,1,5,9,17,109,260,2909,3072,3310,3678,6715,35175,37269,439792,

%T 1400459,1472451,4643918,5683171,44850176,62252861,145631385,

%U 154435765,371056666,1685980637,11196453405,14795372939

%N Coefficients of the generalized continued fraction expansion sqrt(e) = a(1) +a(1)/(a(2) +a(2)/(a(3) +a(3)/(a(4) +a(4)/....))).

%C For more details on Blazys' expansions, see A233582.

%C Compared with simple continued fraction expansion for sqrt(e), this sequence starts soon growing very rapidly.

%H Stanislav Sykora, <a href="/A233584/b233584.txt">Table of n, a(n) for n = 1..1000</a>

%H S. Sykora, <a href="http://dx.doi.org/10.3247/sl4math13.001">Blazys' Expansions and Continued Fractions</a>, Stans Library, Vol.IV, 2013, DOI 10.3247/sl4math13.001

%H S. Sykora, <a href="http://oeis.org/wiki/File:BlazysExpansions.txt">PARI/GP scripts for Blazys expansions and fractions</a>, OEIS Wiki

%F sqrt(e) = 1+1/(1+1/(1+1/(1+1/(5+5/(9+9/(17+17/(109+...))))))).

%t BlazysExpansion[n_, mx_] := Block[{k = 1, x = n, lmt = mx + 1, s, lst = {}}, While[k < lmt, s = Floor[x]; x = 1/(x/s - 1); AppendTo[lst, s]; k++]; lst]; BlazysExpansion[Sqrt@E, 35] (* _Robert G. Wilson v_, May 22 2014 *)

%o (PARI) bx(x, nmax)={local(c, v, k); // Blazys expansion function

%o v = vector(nmax); c = x; for(k=1, nmax, v[k] = floor(c); c = v[k]/(c-v[k]); ); return (v); }

%o bx(exp(1/2), 100) // Execution; use high real precision

%Y Cf. A019774 (sqrt(e)), A058281 (simple continued fraction).

%Y Cf. Blazys' expansions: A233582 (Pi), A233583, A233585, A233586, A233587 and Blazys' continued fractions: A233588, A233589, A233590, A233591.

%K nonn

%O 1,5

%A _Stanislav Sykora_, Jan 06 2014