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A325641 a(1) = 1; for n > 1, a(n) = n/d for the least divisor d > 1 of n such that A048720(d,k) = n for some k.

%I A325641 #7 May 11 2019 18:33:29
%S A325641 1,1,1,2,1,3,1,4,3,5,1,6,1,7,5,8,1,9,1,10,3,11,1,12,1,13,9,14,1,15,1,
%T A325641 16,11,17,5,18,1,19,13,20,1,21,1,22,15,23,1,24,7,25,17,26,1,27,1,28,
%U A325641 19,29,1,30,1,31,21,32,13,33,1,34,1,35,1,36,1,37,25,38,1,39,1,40,1,41,1,42,17,43,1,44,1,45,1,46,3,47,19
%N A325641 a(1) = 1; for n > 1, a(n) = n/d for the least divisor d > 1 of n such that A048720(d,k) = n for some k.
%H A325641 Antti Karttunen, <a href="/A325641/b325641.txt">Table of n, a(n) for n = 1..16384</a>
%H A325641 Antti Karttunen, <a href="/A325641/a325641.txt">Data supplement: n, a(n) computed for n = 1..65537</a>
%H A325641 <a href="/index/Ge#GF2X">Index entries for sequences related to polynomials in ring GF(2)[X]</a>
%F A325641 a(n) = n / A325643(n).
%o A325641 (PARI) A325641(n) = if(1==n,n, my(p = Pol(binary(n))*Mod(1, 2)); fordiv(n,d,if((d>1),my(q = Pol(binary(d))*Mod(1, 2)); if(0==(p%q), return(n/d)))));
%Y A325641 Cf. A048720, A325642, A325643.
%Y A325641 Cf. A325559 (positions of ones after the initial 1).
%K A325641 nonn
%O A325641 1,4
%A A325641 _Antti Karttunen_, May 11 2019