cp's OEIS Frontend

A368239 Irregular table of nonnegative integers T(n, k), n >= 0, k = 1..A080100(n), read by rows; the 1's in the binary expansion of n exactly match the 1's in the balanced ternary expansions of the terms in the n-th row.

%I A368239 #11 Dec 19 2023 12:51:59
%S A368239 0,1,2,3,4,5,6,8,9,7,10,11,12,13,14,15,17,18,23,24,26,27,16,19,25,28,
%T A368239 20,21,29,30,22,31,32,33,35,36,34,37,38,39,40,41,42,44,45,50,51,53,54,
%U A368239 68,69,71,72,77,78,80,81,43,46,52,55,70,73,79,82,47,48,56,57,74,75,83,84
%N A368239 Irregular table of nonnegative integers T(n, k), n >= 0, k = 1..A080100(n), read by rows; the 1's in the binary expansion of n exactly match the 1's in the balanced ternary expansions of the terms in the n-th row.
%C A368239 As a flat sequence, this is a permutation of the nonnegative integers with inverse A368240.
%H A368239 Rémy Sigrist, <a href="/A368239/b368239.txt">Table of n, a(n) for n = 0..9841</a> (rows for n = 0..2^9-1 flattened)
%H A368239 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>
%F A368239 T(n, 1) = A147991(n) for any n > 0.
%F A368239 T(n, A080100(n)) = A005836(n + 1).
%F A368239 A343228(T(n, k)) = n.
%e A368239 Table T(n, k) begins:
%e A368239     0;
%e A368239     1;
%e A368239     2, 3;
%e A368239     4;
%e A368239     5, 6, 8, 9;
%e A368239     7, 10;
%e A368239     11, 12;
%e A368239     13;
%e A368239     14, 15, 17, 18, 23, 24, 26, 27;
%e A368239     16, 19, 25, 28;
%e A368239     20, 21, 29, 30;
%e A368239     22, 31;
%e A368239     32, 33, 35, 36;
%e A368239     34, 37;
%e A368239     38, 39;
%e A368239     40;
%e A368239     ...
%o A368239 (PARI) row(n) = { my (r = [0], b = binary(n)); for (k = 1, #b, r = [3*v+b[k]|v<-r]; if (b[k]==0, r = concat(r, [v-1|v<-r]););); Set(r); }
%Y A368239 See A368225 for a similar sequence.
%Y A368239 Cf. A005836, A080100, A147991, A343228, A368240 (inverse).
%K A368239 nonn,tabf,base
%O A368239 0,3
%A A368239 _Rémy Sigrist_, Dec 18 2023