A030530 n appears A070939(n) times.

0, 1, 2, 2, 3, 3, 4, 4, 4, 5, 5, 5, 6, 6, 6, 7, 7, 7, 8, 8, 8, 8, 9, 9, 9, 9, 10, 10, 10, 10, 11, 11, 11, 11, 12, 12, 12, 12, 13, 13, 13, 13, 14, 14, 14, 14, 15, 15, 15, 15, 16, 16, 16, 16, 16, 17, 17, 17, 17, 17, 18, 18, 18, 18, 18, 19, 19, 19, 19, 19, 20, 20, 20, 20, 20, 21, 21, 21

Offset

0,3

Links

Reinhard Zumkeller, Table of n, a(n) for n = 0..10000

Formula

A030190(n) = T(a(n), A083652(a(n))-n-1), T as defined in A083651.

a(A083652(k)) = k+1.

Sum_{n>=1} (-1)^(n+1)/a(n) = Sum_{n>=1} (-1)^(n+1)/A053738(n) = 0.90457767... . - Amiram Eldar, Feb 18 2024

Mathematica

Join[{0}, Table[Table[n, IntegerLength[n, 2]], {n, 30}]]//Flatten (* Harvey P. Dale, Oct 20 2016 *)

Prog

(Haskell)
import Data.List (unfoldr)
a030530 n = a030530_list !! (n-1)
a030530_list = 0 : concatMap (\n -> unfoldr
   (\x -> if x == 0 then Nothing else Just (n, div x 2)) n) [1..]
-- Reinhard Zumkeller, Dec 05 2011

Crossrefs

Cf. A030190, A053738, A070939, A083651, A083652.

Sequence in context: A082462 A276581 A005041 * A084500 A084557 A024417

Adjacent sequences: A030527 A030528 A030529 * A030531 A030532 A030533

Keyword

easy,nonn

Author

J. Lowell

Status

approved