OFFSET
1,1
COMMENTS
The rule of construction is: each of the even numbers e(k) = 2*k = 2, 4, 6, 8, 10, ... starts a run of numbers that contains e(k) and a(k)-1 odd numbers not used so far. - R. J. Mathar, Sep 09 2010
LINKS
Lars Blomberg, Table of n, a(n) for n = 1..10000
Eric Angelini, Runs
E. Angelini, Runs [Cached copy, with permission]
EXAMPLE
Blocks with run lengths of 2, 1, 4, etc. are (2,1), (4), (6,3,5,7), (8,9,11,13,15,17), (10,19,21), (12,23,25,27,29), ... - R. J. Mathar, Sep 09 2010
MAPLE
A171087 := proc(n) a := [2, 1] ; modd := 1 ; for p from 2 do rl := op(p, a) ; ev := 2*p ; a := [op(a), ev] ; for o from modd+2 to modd+2*(rl-1) by 2 do a := [op(a), o] ; modd := o ; end do: if nops(a) > n then print(a) ; return; end if; end do: end proc: A171087(100) ; # R. J. Mathar, Sep 09 2010
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Sep 07 2010, based on a posting to the Sequence Fans Mailing List by Eric Angelini, Aug 23 2010
EXTENSIONS
More terms from R. J. Mathar and John W. Layman, Sep 09 2010
STATUS
approved