A059942 A059941 translated from binary to decimal.

1, 1, 3, 2, 2, 3, 7, 4, 5, 4, 4, 5, 4, 7, 15, 8, 9, 8, 9, 10, 9, 8, 8, 9, 10, 9, 8, 9, 8, 15, 31, 16, 17, 16, 19, 16, 17, 16, 17, 18, 21, 16, 17, 18, 17, 16, 16, 17, 18, 17, 16, 21, 18, 17, 16, 17, 16, 19, 16, 17, 16, 31, 63, 32, 33, 32, 35, 32, 33, 32, 35, 36, 33, 32, 35, 32, 33, 32

Offset: 1

Author

Henry Bottomley, Feb 14 2001

Keywords

• base
• nonn

Examples

			a(35)=19 since A059941(35)=10011.
		

Links

• Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Programs

Haskell

import Data.List (inits, tails)
a059942 n = a059942_list !! (n-1)
a059942_list = map (foldr (\d v -> v * 2 + d) 0) $ f a030341_tabf where
   f (xs:xss)
     | 0 `elem` xs = f xss
     | otherwise = map fromEnum (zipWith (==)
                   (tail $ inits xs) (reverse $ init $ tails xs)) : f xss
-- Reinhard Zumkeller, Apr 03 2014

Mathematica

a[n_] := (id = Drop[ IntegerDigits[n+1, 2], 1]+1; an = {}; Do[ PrependTo[an, If[Take[id, k] == Take[id, -k], 1, 0]], {k, 1, Length[id]}]; FromDigits[an, 2]); Table[a[n], {n, 1, 78}](* Jean-François Alcover, Nov 21 2011 *)

Formula

a(n) =A059943(n)/2

Extensions

Offset fixed by Reinhard Zumkeller, Apr 03 2014