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!)
A305762 a(0) = 24, a(n) = 2^(max(0, min(3, p - 1))) * 3^(max(0, min(1, q - 1))) where n = 2^p * 3^q * 5^r * ... . 2
24, 1, 1, 1, 2, 1, 1, 1, 4, 3, 1, 1, 2, 1, 1, 1, 8, 1, 3, 1, 2, 1, 1, 1, 4, 1, 1, 3, 2, 1, 1, 1, 8, 1, 1, 1, 6, 1, 1, 1, 4, 1, 1, 1, 2, 3, 1, 1, 8, 1, 1, 1, 2, 1, 3, 1, 4, 1, 1, 1, 2, 1, 1, 3, 8, 1, 1, 1, 2, 1, 1, 1, 12, 1, 1, 1, 2, 1, 1, 1, 8, 3, 1, 1, 2, 1, 1, 1, 4, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Seiichi Manyama, Table of n, a(n) for n = 0..10000

FORMULA

a(n+144) = a(n).

a(n) = gcd(24, n/gcd(6,n)). - Andrew Howroyd, Jul 24 2018

PROG

(PARI) a(n)=gcd(24, n/gcd(6, n)) \\ Andrew Howroyd, Jul 24 2018

(Ruby)

require 'prime'

def A305762(n)

  return 24 if n == 0

  s = 1

  s *= 3 if n % 9 == 0

  n.prime_division.each{|i|

    s *= 2 ** [3, (i[1] - 1)].min if i[0] == 2

  }

  s

end

p (0..144).map{|i| A305762(i)}

CROSSREFS

Cf. A305756.

Sequence in context: A174560 A267427 A040581 * A040582 A102914 A040583

Adjacent sequences:  A305759 A305760 A305761 * A305763 A305764 A305765

KEYWORD

nonn,mult

AUTHOR

Seiichi Manyama, Jun 10 2018

EXTENSIONS

Keyword:mult added by Andrew Howroyd, Jul 24 2018

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 June 23 01:31 EDT 2021. Contains 345394 sequences. (Running on oeis4.)