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Doudna sequence permuted by Blue code: a(n) = A005940(1+A193231(n)).
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%I #16 Oct 06 2023 21:23:41

%S 1,2,4,3,6,5,9,8,16,27,25,18,15,12,10,7,14,11,21,20,35,30,24,45,81,32,

%T 54,125,36,75,49,50,100,147,121,98,225,72,150,245,625,162,64,243,250,

%U 343,375,108,33,28,22,13,40,63,55,42,90,175,135,48,77,70,60,105,210,385,315,120,143,154,140,231,525,180

%N Doudna sequence permuted by Blue code: a(n) = A005940(1+A193231(n)).

%H Antti Karttunen, <a href="/A366263/b366263.txt">Table of n, a(n) for n = 0..16383</a>

%H <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>

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

%F a(n) = A332450(A005940(1+n)).

%F For all n >= 0, A001222(a(n)) = A234022(n) and A046523(a(n)) = A286601(n).

%F For all n >= 1, A055396(a(n)) = A277818(n) = 1+A268389(n).

%o (PARI)

%o A005940(n) = { my(p=2, t=1); n--; until(!n\=2, if((n%2), (t*=p), p=nextprime(p+1))); t };

%o A193231(n) = { my(x='x); subst(lift(Mod(1, 2)*subst(Pol(binary(n), x), x, 1+x)), x, 2) };

%o A366263(n) = A005940(1+A193231(n));

%Y Cf. A005940, A193231, A234022, A268389, A277818, A286601, A286602, A332450, A366264 (inverse map).

%Y Cf. also A365810, A366260, A366275.

%K nonn,look

%O 0,2

%A _Antti Karttunen_, Oct 06 2023