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Permutation of natural numbers induced when A245704 is restricted to {1} and binary codes for polynomials reducible over GF(2): a(1) = 1, a(n) = A062298(A245704(A091242(n-1))).
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%I #9 Aug 18 2014 00:53:22

%S 1,2,3,4,5,7,9,6,10,13,16,8,11,14,17,22,26,15,19,20,23,27,34,39,25,12,

%T 29,31,35,40,50,24,56,37,21,43,46,38,51,57,70,48,36,78,53,33,61,18,65,

%U 55,71,79,95,67,52,30,106,75,49,42,85,54,28,89,77,96,107,74,126,92,73,45,141,98,101,69,59,116,76,41,120,105

%N Permutation of natural numbers induced when A245704 is restricted to {1} and binary codes for polynomials reducible over GF(2): a(1) = 1, a(n) = A062298(A245704(A091242(n-1))).

%H Antti Karttunen, <a href="/A245820/b245820.txt">Table of n, a(n) for n = 1..10001</a>

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

%F a(1) = 1, and for n > 1, a(n) = 1 + A245704(n-1).

%F a(1) = 1, and for n > 1, a(n) = A062298(A245704(A091242(n-1))). [Induced when A245704 is restricted to {1} and binary codes for polynomials reducible over GF(2)].

%F a(1) = 1, and for n > 1, a(n) = A036234(A245704(A014580(n-1))). [Induced also when A245703 is restricted to {1} and other binary codes for polynomials not reducible over GF(2)].

%F As a composition of related permutations:

%F a(n) = A245816(A245813(n)).

%o (PARI)

%o A245820(n) = if(1==n, 1, 1 + A245704(n-1));

%o for(n=1, 10001, write("b245820.txt", n, " ", A245820(n))); \\ The rest of code can be found in A245704.

%o (Scheme, three different implementations)

%o (define (A245820 n) (if (<= n 1) n (+ 1 (A245704 (- n 1)))))

%o (define (A245820 n) (if (<= n 1) n (A062298 (A245704 (A091242 (- n 1))))))

%o (define (A245820 n) (if (<= n 1) n (A036234 (A245704 (A014580 (- n 1))))))

%Y Inverse: A245819.

%Y Related permutations: A245704, A245813, A245816.

%Y Cf. A014580, A036234, A062298, A091242.

%K nonn

%O 1,2

%A _Antti Karttunen_, Aug 16 2014