[seqfan] Re: Extended with a pair of integers

Eric Angelini Eric.Angelini at kntv.be
Sat Oct 11 20:59:00 CEST 2014

```Sorry Franklin and Maximilian :-((

Catapulté de mon aPhone

> Le 11 oct. 2014 à 20:13, "M. F. Hasler" <oeis at hasler.fr> a écrit :
>
> Eric,
> Nice idea, but already there: A167151 (with correct 18+8=26).
> --  Maximilian
>
>> On Sat, Oct 11, 2014 at 12:17 PM, Eric Angelini <Eric.Angelini at kntv.be> wrote:
>>
>> Hello SeqFans,
>> S starts with 1 and is always extended with a pair of integers:
>> - the first integer of the pair is the smallest integer not already in S;
>> - the second integer is the sum of the two integers that preceed it.
>>
>> S=1
>> S=1,2,3,
>> S=1,2,3,4,7
>> S=1,2,3,4,7,5,12
>> S=1,2,3,4,7,5,12,6,18
>> S=1,2,3,4,7,5,12,6,18,8,24
>> S=1,2,3,4,7,5,12,6,18,8,24,9,33
>> S=1,2,3,4,7,5,12,6,18,8,24,9,33,10,43
>> etc.
>> S is a permutation of the intergers > 0
>> Every integer having an odd position in S
>> is the sum of the two integers before it
>> and the absolute difference of the two
>> integers after it (except for 1, the first term of S):
>> 3, for instance, is 1+2 and also |4-7|
>> Best,
>> É.
>
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```