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A245819 Permutation of natural numbers induced when A245703 is restricted to nonprime numbers: a(n) = 1+A091245(A245703(A018252(n))).

%I A245819 #16 Apr 01 2025 17:51:14
%S A245819 1,2,3,4,5,8,6,12,7,9,13,26,10,14,18,11,15,48,19,20,35,16,21,32,25,17,
%T A245819 22,63,27,56,28,138,46,23,29,43,34,38,24,30,80,60,36,88,72,37,167,42,
%U A245819 59,31,39,55,45,62,50,33,40,100,77,320,47,92,109,90,49,201,54,98,76,41,51
%N A245819 Permutation of natural numbers induced when A245703 is restricted to nonprime numbers: a(n) = 1+A091245(A245703(A018252(n))).
%H A245819 Antti Karttunen, <a href="/A245819/b245819.txt">Table of n, a(n) for n = 1..10001</a>
%H A245819 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>
%F A245819 a(1) = 1, and for n > 1, a(n) = 1 + A245703(n-1).
%F A245819 a(n) = 1+A091245(A245703(A018252(n))). [Induced when A245703 is restricted to nonprime numbers].
%F A245819 a(n) = 1+A091226(A245703(A008578(n))). [Induced also when A245703 is restricted to noncomposite numbers].
%F A245819 As a composition of related permutations:
%F A245819 a(n) = A245814(A245815(n)).
%o A245819 (PARI) \\ The rest of code can be found in A245703.
%o A245819 A245819(n) = if(1==n, 1, 1 + A245703(n-1));
%o A245819 (Scheme)
%o A245819 (define (A245819 n) (if (<= n 1) n (+ 1 (A245703 (- n 1)))))
%o A245819 (Scheme)
%o A245819 (define (A245819 n) (+ 1 (A091245 (A245703 (A018252 n)))))
%o A245819 (Scheme)
%o A245819 (define (A245819 n) (+ 1 (A091226 (A245703 (A008578 n)))))
%Y A245819 Inverse: A245820.
%Y A245819 Related permutations: A245703, A245814, A245815.
%Y A245819 Cf. A008578, A018252, A091226, A091245.
%K A245819 nonn
%O A245819 1,2
%A A245819 _Antti Karttunen_, Aug 16 2014