This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A175090 Composites c with result 0 under iterations of {r mod (max prime p <= r)} starting at r = c. 2
 9, 10, 15, 16, 21, 22, 25, 26, 28, 33, 34, 36, 39, 40, 45, 46, 49, 50, 52, 55, 56, 58, 63, 64, 66, 69, 70, 75, 76, 78, 81, 82, 85, 86, 88, 91, 92, 94, 96, 99, 100, 105, 106, 111, 112, 115, 116, 118, 120, 122, 123, 124, 126, 129, 130, 133, 134, 136, 141, 142 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Intersection of A002808 and A175089. Composites c such that A121559(c) = 0. - Michel Marcus, Aug 22 2014 LINKS Robert Israel, Table of n, a(n) for n = 1..10000 EXAMPLE Iteration procedure for a(3) = 15: 15 mod 13 = 2, 2 mod 2 = 0. MAPLE g:= proc(x) if isprime(x) then 0 else x mod prevprime(x) fi end proc: f:= proc(x) local y; y:= x; while y > 1 do y:= g(y) od; y = 0 end proc: select(not(isprime) and f, [\$4..200]); # Robert Israel, Feb 09 2015 MATHEMATICA Composites := Select[Range[2, 200], ! PrimeQ[#] &]; Select[Composites, PrimeQ[# - NextPrime[#, -1]] &] (* Carlos Eduardo Olivieri, Feb 09 2015 *) CROSSREFS Cf. A007917 and A064722 (both for the iterations). Sequence in context: A114844 A194593 A005381 * A197113 A099616 A073829 Adjacent sequences:  A175087 A175088 A175089 * A175091 A175092 A175093 KEYWORD nonn AUTHOR Jaroslav Krizek, Jan 28 2010 EXTENSIONS Missing term 55 inserted, more terms added, Michel Marcus, Aug 22 2014 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.

Last modified February 20 22:51 EST 2019. Contains 320362 sequences. (Running on oeis4.)