[seqfan] Re: 0-additive and first differences

[M. F. Hasler]

On Wed, May 13, 2015 at 12:36 PM, Eric Angelini <Eric.Angelini at kntv.be> wrote:
> Hello SeqFans,
> This is (I hope) the lexico-first 0-additive seq such that
> sequence and first differences list all positive numbers
> exactly once:
>
>    S = 1, 3, 7, 12, 18, 26, 17, 28, 41, 51, 37, 22, 47, ...
> diff    2  4   5   6   8   9  11  13  10  14  15  25

I'm not sure what means 0-additive but there is
oeis.org/A140778 :
a(n) is the smallest positive integer such that no number occurs twice
in the sequence and its absolute first differences.
1, 3, 7, 12, 18, 8, 17, 28, 13, 27, 43, 19, 39, 60, 22, 45, 70, 26,
55, 85, 31, 63, 96, 34, 69, ...

(which has an 8 after the 12)
I add my PARI code there.

Maximilian