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A193652 A020988 and A007583 interleaved. 7
0, 1, 2, 3, 10, 11, 42, 43, 170, 171, 682, 683, 2730, 2731, 10922, 10923, 43690, 43691, 174762, 174763, 699050, 699051, 2796202, 2796203, 11184810, 11184811, 44739242, 44739243, 178956970, 178956971, 715827882, 715827883, 2863311530, 2863311531, 11453246122 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

a(2*n) = A020988(n), a(2*n+1) = a(2*n) + 1 = A007583(n);

apart from initial zero, record values in A048985: a(n)=A048985(A029744(n)) and a(n)<A048985(m) for m<A029744(n).

LINKS

Table of n, a(n) for n=0..34.

Index entries for linear recurrences with constant coefficients, signature (0,5,0,-4).

FORMULA

a(n) = 2 * (4^floor(n/2) - 1) / 3 + n mod 2.

G.f.: ( -x*(-1-2*x+2*x^2) ) / ( (x-1)*(2*x+1)*(2*x-1)*(1+x) ). - R. J. Mathar, Feb 19 2015

MAPLE

A193652 := proc(n)

        if type (n, 'even') then

                A020988(n/2) ;

        else

                A007583(floor(n/2)) ;

        end if;

end proc: # R. J. Mathar, Jul 20 2016

CROSSREFS

Sequence in context: A307034 A081868 A212103 * A092986 A295577 A325256

Adjacent sequences:  A193649 A193650 A193651 * A193653 A193654 A193655

KEYWORD

nonn,easy

AUTHOR

Reinhard Zumkeller, Aug 08 2011

EXTENSIONS

Terms corrected. - R. J. Mathar, Feb 19 2015

STATUS

approved

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Last modified May 18 06:28 EDT 2021. Contains 343994 sequences. (Running on oeis4.)