1,2

Note that A002865 gives the number of entries per column.

Table of n, a(n) for n=1..38.

Table A140691 begins

1..2..4..8..16..32

..3..5..9..17..33

.....7.11..19..35

.......15..23..39

...........31..47

...............63

.................

........6..10..18

...........13..21

...............27

since each matching case, say x, is generated by the rule "2x+1",

only the even cases map to cyclic partitions; so the sequence begins

...............12

...............14

Cf. A002865, A140691.

Sequence in context: A269382 A253886 A253885 * A048640 A242353 A277331

Adjacent sequences: A140689 A140690 A140691 * A140693 A140694 A140695

nonn

Alford Arnold, May 23 2008

approved