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A123170 Continued fraction for (sqrt(2)+1/sqrt(2))*tanh(1/sqrt(2)). 0
1, 3, 2, 3, 21, 6, 33, 8, 1, 2, 4, 1, 2, 11, 57, 14, 69, 16, 1, 2, 8, 1, 2, 19, 93, 22, 105, 24, 1, 2, 12, 1, 2, 27, 129, 30, 141, 32, 1, 2, 16, 1, 2, 35, 165, 38, 177, 40, 1, 2, 20, 1, 2, 43, 201, 46, 213, 48, 1, 2, 24, 1, 2, 51, 237, 54, 249, 56, 1, 2, 28, 1, 2, 59, 273, 62, 285, 64 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

REFERENCES

J. Borwein and D. Bailey, Mathematics by Experiment, Plausible Reasoning in the 21st Century, A. K. Peters, p. 77

LINKS

Table of n, a(n) for n=1..78.

FORMULA

For n>1 a(10n-9)=4n-4, a(10n-8)=1, a(10n-7)=2, a(10n-4)=8n-5, a(10n-5)=36n-15, a(10n-4)=8n-2, a(10n-3)=36n-3, a(10n-2)=8n, a(10n-1)=1, a(10n)=2.

Empirical g.f.: x*(2*x^21 +x^20 -2*x^19 -x^18 +3*x^16 +2*x^15 +15*x^14 +5*x^13 -2*x^12 -5*x^11 +2*x^10 +2*x^9 +x^8 +8*x^7 +33*x^6 +6*x^5 +21*x^4 +3*x^3 +2*x^2 +3*x +1) / (x^20 -2*x^10 +1). - Colin Barker, Jun 28 2013

MATHEMATICA

ContinuedFraction[3Tanh[1/Sqrt[2]]/Sqrt[2], 78] - Benoit Cloitre, Oct 02 2006

CROSSREFS

Sequence in context: A298594 A092950 A059239 * A253381 A091806 A248244

Adjacent sequences:  A123167 A123168 A123169 * A123171 A123172 A123173

KEYWORD

nonn,cofr

AUTHOR

Benoit Cloitre, Oct 02 2006

STATUS

approved

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Last modified May 25 11:27 EDT 2020. Contains 334592 sequences. (Running on oeis4.)