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A366260 Doudna sequence permuted by May code: a(n) = A005940(1+A303767(n)).

%I A366260 #10 Oct 06 2023 08:34:48
%S A366260 1,2,4,3,9,5,6,8,16,7,10,12,15,27,25,18,54,11,14,20,21,45,35,30,24,32,
%T A366260 49,50,36,75,81,125,625,13,22,28,33,63,55,42,40,48,77,70,60,105,135,
%U A366260 175,90,162,121,98,100,147,225,245,150,72,64,343,250,108,375,243,729,17,26,44,39,99,65,66,56,80,91,110
%N A366260 Doudna sequence permuted by May code: a(n) = A005940(1+A303767(n)).
%H A366260 Antti Karttunen, <a href="/A366260/b366260.txt">Table of n, a(n) for n = 0..16384</a>
%H A366260 <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>
%H A366260 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>
%o A366260 (PARI)
%o A366260 A005940(n) = { my(p=2, t=1); n--; until(!n\=2, if((n%2), (t*=p), p=nextprime(p+1))); t };
%o A366260 A209229(n) = (n && !bitand(n,n-1));
%o A366260 A053644(n) = { my(k=1); while(k<=n, k<<=1); (k>>1); }; \\ From A053644
%o A366260 A303767(n) = if(!n,n,if(A209229(n),n+A303767(n-1),A053644(n)+A303767(n-A053644(n)-1)));
%o A366260 A366260(n) = A005940(1+A303767(n));
%Y A366260 Cf. A005940, A303767, A366261, A366262.
%Y A366260 Cf. also A243353, A366263.
%K A366260 nonn
%O A366260 0,2
%A A366260 _Antti Karttunen_, Oct 05 2023