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A259858 A bisection of A002083. 2
1, 1, 3, 11, 42, 165, 654, 2605, 10398, 41550, 166116, 664299, 2656866, 10626810, 42505932, 170021123, 680079282, 2720306730, 10881206124, 43524782946, 174099048684, 696396028620, 2785583782248, 11142334464693, 44569336530174, 178277343463830, 713109368541588 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..26.

FORMULA

a(0)=a(1)=1; a(2)=3; a(n) = 4*a(n-1) + ((-1)^(n-1)-3)/2 * a(floor((n-1)/2)). - Carl R. White, Oct 06 2017

MAPLE

A259858 := proc(n)

    A002083(2*n+1) ;

end proc:

seq(A259858(n), n=0..30) ; # R. J. Mathar, Jul 09 2015

MATHEMATICA

a[n_] := a[n] = If[n < 3, 1 + 2 Boole@ PrimeQ@ n, 4 a[n - 1] + ((-1)^(n - 1) - 3)/2*a[Floor[(n - 1)/2]]]; Array[a, 27, 0] (* Michael De Vlieger, Oct 06 2017 *)

CROSSREFS

Cf. A002083, A245094.

Sequence in context: A180907 A143464 A270561 * A117641 A200030 A084782

Adjacent sequences:  A259855 A259856 A259857 * A259859 A259860 A259861

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Jul 07 2015

STATUS

approved

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Last modified January 17 09:54 EST 2020. Contains 330949 sequences. (Running on oeis4.)