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

 

Logo

Thanks to everyone who made a donation during our annual appeal!
To see the list of donors, or make a donation, see the OEIS Foundation home page.

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A085075 Smallest number a(n) == -1 (mod n) such that the prime signature of n and a(n) is the same, or 0 if no such number exists. 0
3, 2, 0, 19, 35, 13, 343, 0, 39, 43, 275, 103, 55, 14, 0, 67, 539, 37, 99, 62, 21, 137, 2375, 49, 51, 4913, 279, 173, 2639, 61, 0, 65, 33, 34, 0, 73, 265, 38, 999, 163, 1595, 257, 175, 44, 91, 281, 29375, 0, 99, 203, 207, 211, 2375, 219, 783, 341, 57, 353, 14399, 487, 123 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

LINKS

Table of n, a(n) for n=2..62.

EXAMPLE

a(6) =35 = 6*6 -1 = 3*13 and 6 = 2*3 are both of prime signature p*q, where p and q are primes.

CROSSREFS

Cf. A085074.

Sequence in context: A111541 A244134 A105629 * A321518 A267883 A333437

Adjacent sequences:  A085072 A085073 A085074 * A085076 A085077 A085078

KEYWORD

nonn

AUTHOR

Amarnath Murthy, Jul 01 2003

EXTENSIONS

More terms from David Wasserman, Jan 12 2005

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 January 16 10:52 EST 2021. Contains 340206 sequences. (Running on oeis4.)