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

 

Logo

The OEIS is looking to hire part-time people to help edit core sequences, upload scanned documents, process citations, fix broken links, etc. - Neil Sloane, njasloane@gmail.com

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A213013 (2^3^4^5^...^n) mod n 2
0, 2, 0, 2, 2, 1, 0, 8, 2, 2, 8, 5, 8, 2, 0, 2, 8, 18, 12, 8, 2, 16, 8, 2, 18, 26, 8, 11, 2, 2, 0, 2, 2, 22, 8, 31, 18, 5, 32, 2, 8, 27, 24, 17, 16, 8, 32, 43, 2, 2, 44, 45, 26, 2, 8, 56, 40, 47, 32, 33, 2, 8, 0, 57, 2, 5, 36, 62, 22, 60, 8, 1, 68, 2, 56, 57, 44, 8, 32, 80, 2, 2, 8, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,2

COMMENTS

a(n) = 0 iff n is a power of 2.

LINKS

Max Alekseyev, Table of n, a(n) for n = 2..1000

PROG

(PARI) { a(n, m=n, s=2) = local(g); if(s==n, return(n%m)); g=factor(gcd(s, m)); for(i=1, matsize(g)[1], g[i, 2]=valuation(m, g[i, 1]); m\=g[i, 1]^g[i, 2]); g=prod(i=1, matsize(g)[1], g[i, 1]^g[i, 2]); lift( chinese( Mod(0, g), Mod(s, m)^a(n, eulerphi(m), s+1) )) }

CROSSREFS

A variant of A092188.

Sequence in context: A058728 A143751 A158950 * A242667 A059581 A236998

Adjacent sequences:  A213010 A213011 A213012 * A213014 A213015 A213016

KEYWORD

nonn

AUTHOR

Max Alekseyev, Jun 02 2012

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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified May 27 07:59 EDT 2017. Contains 287203 sequences.