OFFSET
1,2
COMMENTS
This sequence is a permutation of the positive integers.
LINKS
Jean-Marc Falcoz, Table of n, a(n) for n = 1..10002
EXAMPLE
The sequence starts with 1,2,3,5,4,9,13,6,19,25,7,... and we see that:
a(1) = 1 and a(2) = 2 being of opposite parity are followed by their sum (3);
a(2) = 2 and a(3) = 3 being of opposite parity are followed by their sum (5);
a(3) = 3 and a(4) = 5 being of the same parity are followed by the smallest term not yet in the sequence (4);
a(4) = 5 and a(5) = 4 being of opposite parity are followed by their sum (9);
a(5) = 4 and a(6) = 9 being of opposite parity are followed by their sum (13);
a(6) = 9 and a(7) = 13 being of the same parity are followed by the smallest term not yet in the sequence (6);
etc.
CROSSREFS
KEYWORD
AUTHOR
Eric Angelini and Jean-Marc Falcoz, Mar 20 2019
STATUS
approved