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A181363 1 followed by the primes, interleaved recursively. 4
1, 1, 2, 1, 3, 2, 5, 1, 7, 3, 11, 2, 13, 5, 17, 1, 19, 7, 23, 3, 29, 11, 31, 2, 37, 13, 41, 5, 43, 17, 47, 1, 53, 19, 59, 7, 61, 23, 67, 3, 71, 29, 73, 11, 79, 31, 83, 2, 89, 37, 97, 13, 101, 41, 103, 5, 107, 43, 109, 17, 113, 47, 127, 1, 131, 53, 137, 19, 139, 59, 149, 7, 151, 61 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

a(2*n-1) = A008578(n); a(2*n+1) = A000040(n);

a((2*n-1)*2^k) = A008578(n), k >= 0;

a(2^k) = 1, k >= 0; a(2^k - 1) = A051438(k), k > 0.

LINKS

R. Zumkeller, Table of n, a(n) for n = 1..8191

FORMULA

a(n) = if even n then a(n/2) else A008578((n+1)/2).

a(n) = A008578(A025480(n-1)+1). - Reinhard Zumkeller, Mar 22 2014

EXAMPLE

Initial values, seen as a binary tree:

................................. 1

................ 1 _______________________________ 2

........ 1 _____________ 3 .............. 2 ______________ 5

... 1 _____ 7 ..... 3 ______ 11 .... 2 ______ 13 .... 5 ______ 17

.. 1__19...7__23...3__29...11__31...2__37...13__41...5__43...17__47

PROG

(Haskell)

import Data.List (transpose)

a181363 n = a181363_list !! (n-1)

a181363_list = concat $ transpose [a008578_list, a181363_list]

-- Reinhard Zumkeller, Mar 22 2014, Oct 20 2011, Oct 16 2010

CROSSREFS

Sequence in context: A321272 A321270 A030067 * A105800 A105602 A111079

Adjacent sequences:  A181360 A181361 A181362 * A181364 A181365 A181366

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Oct 16 2010

STATUS

approved

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Last modified September 28 01:20 EDT 2020. Contains 337388 sequences. (Running on oeis4.)