login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A125715 a(1)=1. a(n) = the smallest positive integer not occurring earlier in the sequence such that (sum{k=1 to n-1} a(k)) is congruent to a(n) (mod n). 3

%I #16 Oct 10 2019 15:53:51

%S 1,3,4,8,6,10,11,19,17,9,22,2,21,7,5,33,25,23,36,42,31,27,40,18,20,24,

%T 32,48,51,55,30,72,26,64,37,15,43,63,103,143,16,44,59,45,60,90,56,80,

%U 79,75,14,96,52,68,100,108,65,91,84,128,94,146,61,13,110,176,107,99,12,114

%N a(1)=1. a(n) = the smallest positive integer not occurring earlier in the sequence such that (sum{k=1 to n-1} a(k)) is congruent to a(n) (mod n).

%C This sequence seems likely to be a permutation of the positive integers.

%H Ferenc Adorjan, <a href="/A125715/b125715.txt">Table of n,a(n) for n=1,10000</a>

%H Ferenc Adorjan, <a href="http://web.t-online.hu/fadorjan/l_quet.pdf">Some characteristics of _Leroy Quet_'s permutation sequences</a>

%t f[l_List] := Block[{n = Length[l] + 1, k = Mod[Plus @@ l, n, 1]},While[MemberQ[l, k], k += n];Append[l, k]];Nest[f, {1}, 70] (* _Ray Chandler_, Feb 04 2007 *)

%o (PARI) {Quet_p1(n)=/* Permutation sequence a'la _Leroy Quet_, A125715 */local(x=[1],s=1,k=0,w=1); for(i=2,n,if((k=s%i)==0,k=i);while(bittest(w,k-1)>0,k+=i);x=concat(x,k);s+=k;w+=2^(k-1));return(x)}

%K nonn

%O 1,2

%A _Leroy Quet_, Feb 01 2007

%E Extended by _Ray Chandler_, Feb 04 2007

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified August 20 23:19 EDT 2024. Contains 375341 sequences. (Running on oeis4.)