[seqfan] Forbidden digit(s)

Eric Angelini Eric.Angelini at kntv.be
Mon Dec 21 00:41:51 CET 2015

Hello SeqFans,
We want the lexico-first seq S such 
that the digit 0 (zero) doesn't appear
in S, doesn't in a(n)+a(n+1) and doesn't 
in a(n)*a(n+1)

S = 1,2,3,4,7,5,9,6,8,11,12,13,14,17,15,19,18,16,...

The similar seq T forbidding 1 from T, from the
sum and from the product of two consecutive 
terms of T starts, I guess:

T = 0,2,3,20,4,5,40,6,34,8,25,9,23,...

Equivalent seq coulf be computed for 
the forbidden digits 2 to 9.

I was wondering if infinite seq like S and T
are still possible if we forbid two digits in the seq -- or three, etc. 

Catapulté de mon aPhone

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