Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #11 Jul 25 2020 12:02:04
%S 1,3,2,8,5,9,4,6,7,12,10,13,15,11,14,38,20,32,26,53,27,25,33,19,39,40,
%T 18,34,24,28,30,22,36,16,42,37,21,31,48,47,56,23,29,50,35,17,41,44,51,
%U 49,46,54,61,43,52,63,55,45,58,57,59,60,65,68,62,71,69
%N Lexicographically earliest sequence of distinct positive terms such that the sum of two consecutive terms has distinct digits in primorial base.
%C In other words, for any n > 0, a(n) + a(n+1) belongs to A321683.
%H Rémy Sigrist, <a href="/A336478/b336478.txt">Table of n, a(n) for n = 1..10000</a>
%H Rémy Sigrist, <a href="/A336478/a336478.png">Scatterplot of the first 1000000 terms</a>
%H Rémy Sigrist, <a href="/A336478/a336478.gp.txt">PARI program for A336478</a>
%H <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a>
%e The first terms, alongside the primorial representation of a(n)+a(n+1), are:
%e n a(n) prim(a(n)+a(n+1))
%e -- ---- -----------------
%e 1 1 (2,0)
%e 2 3 (2,1)
%e 3 2 (1,2,0)
%e 4 8 (2,0,1)
%e 5 5 (2,1,0)
%e 6 9 (2,0,1)
%e 7 4 (1,2,0)
%e 8 6 (2,0,1)
%e 9 7 (3,0,1)
%e 10 12 (3,2,0)
%e 11 10 (3,2,1)
%e 12 13 (4,2,0)
%e 13 15 (4,1,0)
%e 14 11 (4,0,1)
%o (PARI) See Links section.
%Y Cf. A321683, A322845, A336285.
%K nonn,look,base
%O 1,2
%A _Rémy Sigrist_, Jul 22 2020