login
This site is supported by donations to The OEIS Foundation.
Logo

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A135873 Multiply the positive integers which are coprime to n in order (starting at 1). a(n) is the largest such partial product that is <= n. 1
1, 1, 2, 3, 2, 5, 6, 3, 8, 3, 6, 5, 6, 3, 8, 15, 6, 5, 6, 3, 8, 15, 6, 5, 24, 15, 8, 15, 24, 7, 24, 15, 8, 15, 24, 35, 24, 15, 8, 21, 24, 5, 24, 15, 8, 15, 24, 35, 24, 21, 40, 15, 24, 35, 24, 15, 40, 15, 24, 7, 24, 15, 40, 15, 24, 35, 24, 15, 40, 27, 24, 35, 24, 15, 56, 15, 24, 35, 24 (list; graph; refs; listen; history; internal format)
OFFSET

1,3

EXAMPLE

The positive integers which are coprime to 9 begin: 1,2,4,5,7,8,10,11,... Checking the partial products: 1=1, 1*2=2, 1*2*4 = 8, 1*2*4*5 =40,... 8 is the largest such partial product which is <= 9. So a(9) = 8.

MATHEMATICA

a = {}; For[n = 1, n < 80, n++, p = 1; i = 1; While[p < n, i++; If[GCD[i, n] == 1, p = p*i]]; AppendTo[a, p/i]]; a - Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Feb 06 2008

CROSSREFS

Cf. A135872.

Sequence in context: A066119 A003970 A094443 * A070673 A070669 A164912

Adjacent sequences:  A135870 A135871 A135872 * A135874 A135875 A135876

KEYWORD

nonn

AUTHOR

Leroy Quet Dec 03 2007

EXTENSIONS

More terms from Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Feb 06 2008

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified February 17 09:30 EST 2012. Contains 206009 sequences.