OFFSET

1,3

LINKS

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = A229708(n) if and only if a(n) is prime. - Jonathan Sondow, May 17 2017

EXAMPLE

a(6)=5 because order of 1 is 1 and 2 through 4 are not relatively prime to 6, but 5 has order 2, which is the maximum possible.

MATHEMATICA

Table[Min[

Select[Range[n],

CoprimeQ[#, n] &&

MultiplicativeOrder[#, n] == CarmichaelLambda[n] &]], {n, 1, 100}]

(* Geoffrey Critzer, Jan 04 2015 *)

PROG

(PARI) a(n)=if(n==1, return(1)); if(n<5, return(n-1)); my(o=lcm(znstar(n)[2]), k=1); while(gcd(k++, n)>1 || znorder(Mod(k, n))<o, ); k \\ Charles R Greathouse IV, Jul 31 2013

CROSSREFS

KEYWORD

easy,nonn

AUTHOR

Franklin T. Adams-Watters, Oct 10 2005

STATUS

approved