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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A245708 Permutation of natural numbers, the odd bisection of A245606 incremented by one and halved: a(n) = (1+A245606((2*n)-1))/2.

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%I A245708 #14 Mar 27 2025 21:32:05
%S A245708 1,2,3,5,4,8,6,11,7,14,13,41,10,23,63,20,15,17,9,50,16,26,21,65,45,32,
%T A245708 18,44,30,413,58,95,22,53,12,29,27,38,66,221,52,122,48,77,115,83,748,
%U A245708 179,69,263,25,365,39,113,153,176,130,158,508,1007,247,140,78,242,97,59,33,89,72,68,36,47,49,188,28
%N A245708 Permutation of natural numbers, the odd bisection of A245606 incremented by one and halved: a(n) = (1+A245606((2*n)-1))/2.
%H A245708 Antti Karttunen, <a href="/A245708/b245708.txt">Table of n, a(n) for n = 1..10001</a>
%H A245708 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>
%F A245708 a(n) = (1+A245606((2*n)-1))/2.
%F A245708 As a composition of related permutations:
%F A245708 a(1) = 1, and for n > 1, a(n) = A048673(1+A245606(n-1)).
%F A245708 a(n) = A245608(A245705(n)).
%F A245708 Other identities:
%F A245708 For all n >= 0, a(2^n) = A245608(2^n). Moreover, A245709 gives all such k that a(k) = A245608(k).
%o A245708 (PARI)
%o A245708 A003961(n) = my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); \\ This function from _Michel Marcus_
%o A245708 A245606(n) = if(1==n, 1, if(0==(n%2), 1+A003961(A245606(n/2)), A003961(1+A245606((n-1)/2))));
%o A245708 A245708(n) = (1+A245606((2*n)-1))/2;
%o A245708 for(n=1, 10001, write("b245708.txt", n, " ", A245708(n)))
%o A245708 (Scheme)
%o A245708 (define (A245708 n) (* (/ 1 2) (+ 1 (A245606 (-1+ (* 2 n))))))
%o A245708 (Scheme)
%o A245708 (define (A245708 n) (if (= 1 n) n (A048673 (+ 1 (A245606 (- n 1))))))
%Y A245708 Inverse: A245707.
%Y A245708 Cf. A003961, A048673, A245606, A245608, A245705, A245709.
%K A245708 nonn
%O A245708 1,2
%A A245708 _Antti Karttunen_, Jul 30 2014