A156819 - OEIS

A156819

Last digit d of a(n) is present in a(n+1+d); a(1)=0; a(n+1) is always the smallest available integer not already in the sequence and not leading to a contradiction.

%I #15 Jun 09 2016 21:40:14

%S 0,10,20,30,40,50,60,70,80,90,100,101,1,11,12,13,2,21,3,123,4,5,23,31,

%T 6,14,32,15,7,22,24,16,25,35,8,34,17,9,56,45,41,18,19,28,27,65,26,29,

%U 33,36,38,51,3789,61,37,71,46,91,39,81,42,102,79

%N Last digit d of a(n) is present in a(n+1+d); a(1)=0; a(n+1) is always the smallest available integer not already in the sequence and not leading to a contradiction.

%C The sequence arising when a(n)<a(n+1) is A156818. Thanks to Hans Havermann and Paolo Lava for their remarks.

%H Sean A. Irvine, <a href="/A156819/b156819.txt">Table of n, a(n) for n = 1..10000</a>

%H Eric Angelini, <a href="http://www.cetteadressecomportecinquantesignes.com/LastDigit.htm">LastDigit</a>

%H E. Angelini, <a href="/A156819/a156819.pdf">LastDigit</a> [Cached copy, with permission]

%K base,easy,nonn

%O 1,2

%A _Eric Angelini_, Feb 16 2009

%E More terms from _Sean A. Irvine_, Apr 09 2013