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A084188 a(0)=1, a(n+1) = 2*a(n) + b(n+2), where b(n)=A004539(n) is the n-th bit in the binary expansion of sqrt(2). 3
1, 2, 5, 11, 22, 45, 90, 181, 362, 724, 1448, 2896, 5792, 11585, 23170, 46340, 92681, 185363, 370727, 741455, 1482910, 2965820, 5931641, 11863283, 23726566, 47453132, 94906265, 189812531, 379625062, 759250124 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

Numerators in approximation sqrt(2) ~ a(n)/2^n.

FORMULA

a(n) = floor(sqrt(2)*2^n);

a(n) = A017910(2*n+1). - # Peter Luschny, Sep 20 2011

MAPLE

A084188 := n->floor(sqrt(2)*2^n); # Peter Luschny, Sep 20 2011

PROG

(PARI) a(n)=floor(sqrt(2)<<n) \\ Charles R Greathouse IV, Sep 22 2011

CROSSREFS

Cf. A084185, A084186, A017910.

Sequence in context: A024493 A130781 A071015 * A044432 A033120 A091617

Adjacent sequences:  A084185 A084186 A084187 * A084189 A084190 A084191

KEYWORD

nonn,easy

AUTHOR

Ralf Stephan (ralf(AT)ark.in-berlin.de), May 18 2003

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Last modified February 16 07:39 EST 2012. Contains 205881 sequences.