%I #8 Mar 15 2018 06:19:00
%S 1,2,9,4,5,18,21,8,9,10,33,36,65,42,165,16,17,18,133,20,21,66,69,72,
%T 325,130,81,84,145,330,341,32,33,34,1365,36,37,266,273,40,41,42,129,
%U 132,585,138,329,144,1029,650,1173,260,265,162,165,168,513,290,649
%N a(n) is the least positive multiple of n which is a Fibbinary number (A003714).
%H Rémy Sigrist, <a href="/A300889/b300889.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = n * A300867(n).
%F a(2*n) = 2*a(n).
%F a(n) = n iff n belongs to A003714.
%e The first terms, alongside their binary representation, are:
%e n a(n) binary(a(n))
%e -- ---- ------------
%e 1 1 1
%e 2 2 10
%e 3 9 1001
%e 4 4 100
%e 5 5 101
%e 6 18 10010
%e 7 21 10101
%e 8 8 1000
%e 9 9 1001
%e 10 10 1010
%e 11 33 100001
%e 12 36 100100
%e 13 65 1000001
%e 14 42 101010
%e 15 165 10100101
%e 16 16 10000
%e 17 17 10001
%e 18 18 10010
%e 19 133 10000101
%e 20 20 10100
%o (PARI) a(n) = forstep (k=1, oo, 2, if (bitand(k*n, 2*k*n)==0, return (k*n)))
%Y Cf. A003714, A300867.
%K nonn,base
%O 1,2
%A _Rémy Sigrist_, Mar 14 2018
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