A120229 - OEIS

%I #20 Dec 23 2024 14:53:42

%S 3,6,1,12,15,2,21,24,27,30,33,4,39,42,5,48,51,54,57,60,7,66,69,8,75,

%T 78,9,84,87,10,93,96,11,102,105,108,111,114,13,120,123,14,129,132,135,

%U 138,141,16,147,150,17,156,159,18,165,168,19,174,177,20,183,186,189,192,195

%N Split-floor-multiplier sequence (SFMS) using multipliers 1/3 and 3. The SFMS using multipliers r and s is here introduced: for every positive integer n and positive real number r, let [rn] abbreviate floor(rn). Then SFMS(r, s), where max {r, s} > 1, is the sequence a defined by a(n)=[rn] if [rn] > 0 and is not already in a and a(n) = [sn] otherwise.

%C Self-inverse permutation of the natural numbers.

%D Responses to message "Murthy's sequence A073675" to the seqfan mailing list. The message and responses are dated Feb 02 2006 and relate to generalizations and properties of sequence A073675, which is SFMS(1/2,2).

%H <a href="https://web.archive.org/web/*/http://list.seqfan.eu/oldermail/seqfan-old/2006-February/007226.html">Seqfan: about Murthy's sequence A073675 (1)</a>

%H <a href="https://web.archive.org/web/*/http://list.seqfan.eu/oldermail/seqfan-old/2006-February/007228.html">Seqfan: about Murthy's sequence A073675 (2)</a>

%H <a href="https://web.archive.org/web/*/http://list.seqfan.eu/oldermail/seqfan-old/2006-February/007232.html">Seqfan: about Murthy's sequence A073675 (3)</a>

%H <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>

%F a(n) = [n/3] if this is positive and new, otherwise a(n)=3n.

%e a(1) = 1*3 because [1/3] is not positive.

%e a(2) = 2*3 because [2/3] is not positive.

%e a(3) = 1 = [3*(1/3)].

%e a(4) = 4*3 because [4/3] = a(3), not new.

%Y Cf. A073675, A120230.

%Y Row 3 and column 3 of A059897.

%K nonn,changed

%O 1,1

%A _Clark Kimberling_, Jun 11 2006