A339092 - OEIS

%I #16 Dec 07 2020 01:59:13

%S 2,3,2,3,2,3,2,3,2,-1,-1,-1,-1,13,-1,-1,-1,5,-1,-1,-1,9,12,16,14,-1,

%T -1,-1,-1,-1,-1,17,18,-1,-1,-1,-1,20,-1,13,20,-1,-1,-1,-1,-1,-1,22,18,

%U -1,-1,19,-1,-1,-1,-1,-1,-1,28,-1,-1,32,-1,-1,24,-1,-1,-1,-1,-1,-1,22,-1,-1,-1,-1,30,-1,-1,-1,-1,28

%N Number of steps needed for a(1) = k ("the seed") to reappear in the sequence under the A339091 protocol, for k = 1, 2, 3, 4, ... to n. Else -1 if the seed never reappears.

%C A339091 explains how a(1) = k ("the seed") generates a sequence.

%H Carole Dubois, <a href="/A339092/b339092.txt">Table of n, a(n) for n = 1..20000</a>

%e The seed 1 generates another 1 at step #2 under the A339091 protocol; thus a(1) = 2;

%e The seed 2 generates another 2 at step #3 under the A339091 protocol; thus a(2) = 3;

%e The seed 3 generates another 3 at step #2 under the A339091 protocol; thus a(3) = 2;

%e The seed 4 generates another 4 at step #3 under the A339091 protocol; thus a(4) = 3;

%e The seed 10 doesn't generate any 10 under the A339091 protocol; thus a(10) = -1;

%e The seed 14 generates another 14 at step #13 under the A339091 protocol; thus a(14) = 13; etc.

%Y Cf. A339091 (the protocol), A339093 (the "sterile" seeds producing -1); A339111 (the "fertile" seeds).

%K base,sign

%O 1,1

%A _Eric Angelini_ and _Carole Dubois_, Nov 23 2020