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A227326
a(2n) = 2a(n)+2^(2n), a(2n+1) = 2^(2n+1), a(0)=0.
1
0, 2, 8, 8, 32, 32, 80, 128, 320, 512, 1088, 2048, 4256, 8192, 16640, 32768, 66176, 131072, 263168, 524288, 1050752, 2097152, 4198400, 8388608, 16785728, 33554432, 67125248, 134217728, 268468736, 536870912, 1073807360, 2147483648, 4295099648, 8589934592
OFFSET
0,2
COMMENTS
Simplest sequence of form a(2n)=c*a(n)+f(n), a(2n+1)=g(n) that cannot be easily expressed as a function of A007814(n).
LINKS
FORMULA
a(n) = sum(k=0..A007814(n), 2^(k+n/2^k) ).
PROG
(PARI) a(n)=sum(k=0, valuation(n, 2), 2^(k+n/2^k))
(PARI) a(n)=if(n<1, 0, if(n%2==0, 2*a(n/2)+2^n, 2^n))
(Haskell)
import Data.List (transpose)
a227326 n = a227326_list !! n
a227326_list = 0 : xs where
xs = concat $ transpose
[a004171_list, zipWith (+) (tail a000302_list) (map (* 2) xs)]
-- Reinhard Zumkeller, Jul 08 2013
CROSSREFS
Sequence in context: A180825 A230708 A230739 * A323852 A064231 A181130
KEYWORD
nonn,easy
AUTHOR
Ralf Stephan, Jul 07 2013
STATUS
approved