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A246364 Permutation of natural numbers: a(n) = A064216(A227413(n)).

%I A246364 #10 Aug 27 2014 14:53:23
%S A246364 1,2,5,3,7,11,13,4,6,9,19,14,8,12,29,10,17,31,23,16,41,71,37,44,47,39,
%T A246364 43,42,38,30,26,59,22,34,15,85,53,58,25,130,57,151,61,311,103,69,33,
%U A246364 365,157,111,73,226,74,106,67,370,223,56,97,341,139,122,35,133,55,86,20,145,46,49,21,659,118,36,83,419,127,191,18
%N A246364 Permutation of natural numbers: a(n) = A064216(A227413(n)).
%C A246364 After a(2) = 2, the rest of the even bisection contains only terms of A246261. However, some of the terms of A246261 are also found in the odd bisection, while terms of A246263, apart from 2, all reside in the odd bisection of this sequence.
%H A246364 Antti Karttunen, <a href="/A246364/b246364.txt">Table of n, a(n) for n = 1..4095</a>
%H A246364 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>
%F A246364 a(n) = A064216(A227413(n)).
%o A246364 (PARI)
%o A246364 default(primelimit,(2^31)+(2^30));
%o A246364 A002808(n) = { my(k=-1); while( -n + n += -k + k=primepi(n), ); n }; \\ This function from _M. F. Hasler_
%o A246364 A064989(n) = {my(f); f = factor(n); if((n>1 && f[1,1]==2), f[1,2] = 0); for (i=1, #f~, f[i,1] = precprime(f[i,1]-1)); factorback(f)};
%o A246364 A064216(n) = A064989((2*n)-1);
%o A246364 A227413(n) = if(1==n, 1, if(!(n%2), prime(A227413(n/2)), A002808(A227413((n-1)/2))));
%o A246364 A246364(n) = A064216(A227413(n));
%o A246364 for(n=1, 4095, write("b246364.txt", n, " ", A246364(n)));
%o A246364 (Scheme) (define (A246364 n) (A064216 (A227413 n)))
%Y A246364 Inverse: A246363.
%Y A246364 Related or similar permutations: A064216, A227413, A246366, A246368.
%Y A246364 Cf. A246261, A246263.
%K A246364 nonn
%O A246364 1,2
%A A246364 _Antti Karttunen_, Aug 26 2014