login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A286633 Base-3 {digit+1} product of A254103: a(n) = A006047(A254103(n)). 5
1, 2, 3, 2, 6, 4, 9, 3, 12, 2, 6, 6, 18, 8, 18, 4, 24, 12, 27, 6, 12, 3, 9, 4, 36, 4, 12, 6, 36, 2, 6, 12, 48, 6, 18, 12, 54, 16, 36, 9, 24, 24, 54, 4, 18, 8, 18, 6, 72, 24, 54, 6, 24, 12, 27, 6, 72, 36, 81, 12, 12, 6, 18, 18, 96, 36, 81, 12, 36, 6, 18, 36, 108, 8, 24, 18, 72, 24, 54, 8, 48, 12, 36, 18, 108, 2, 6, 24, 36, 4, 12, 12, 36, 3, 9, 4 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Reflecting the structure of A254103 also this sequence can be represented as a binary tree:

                                     1

                                     |

                  ...................2...................

                 3                                       2

       6......../ \........4                   9......../ \........3

      / \                 / \                 / \                 / \

     /   \               /   \               /   \               /   \

    /     \             /     \             /     \             /     \

  12       2           6       6          18       8          18       4

24  12   27 6        12 3     9 4       36  4    12 6       36  2     6 12

etc.

LINKS

Antti Karttunen, Table of n, a(n) for n = 0..8191

FORMULA

a(n) = A006047(A254103(n)).

For n >= 0, a(A000079(n)) = A042950(n).

PROG

(Scheme) (define (A286633 n) (A006047 (A254103 n)))

(Python)

from sympy.ntheory.factor_ import digits

from operator import mul

def a006047(n):

    d=digits(n, 3)

return reduce(mul, [1 + d[i] for i in range(1, len(d))])

def a254103(n):

    if n==0: return 0

    if n%2==0: return 3*a254103(n/2) - 1

    else: return floor((3*(1 + a254103((n - 1)/2)))/2)

def a(n): return a006047(a254103(n)) # Indranil Ghosh, Jun 06 2017

CROSSREFS

Cf. A000079, A006047, A042950, A254103, A286586, A286587, A286632.

Sequence in context: A161888 A157224 A097914 * A286586 A113710 A286587

Adjacent sequences:  A286630 A286631 A286632 * A286634 A286635 A286636

KEYWORD

nonn,base

AUTHOR

Antti Karttunen, Jun 03 2017

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified September 24 22:46 EDT 2021. Contains 347651 sequences. (Running on oeis4.)