A250472 - OEIS

%I #15 Dec 13 2014 00:41:02

%S 1,2,3,5,4,7,11,6,13,17,8,19,9,10,23,29,12,15,31,14,37,41,16,43,25,18,

%T 47,21,20,53,59,22,27,61,24,67,71,26,35,73,28,79,33,30,83,55,32,39,89,

%U 34,97,101,36,103,107,38,109,45,40,65,49,42,51,113,44,127,85,46,131,137,48,77,57,50,139,149,52,63,151,54,95,157,56,163,121,58,167,69,60

%N Permutation of natural numbers: a(n) = A250470(2*n - 1).

%C For n > 1, a(n) tells which number is located immediately above n in the sieve of Eratosthenes (see A083140, A083221) in the same column of the sieve that contains 2n - 1.

%H Antti Karttunen, <a href="/A250472/b250472.txt">Table of n, a(n) for n = 1..4096</a>

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

%F a(1) = 1, a(n) = A083221(A055396(2*n - 1)-1, A078898(2*n - 1)).

%F a(n) = A250470(2*n - 1).

%o (Scheme, two alternatives)

%o (define (A250472 n) (A250470 (+ n n -1)))

%o (define (A250472 n) (if (= 1 n) n (A083221bi (- (A055396 (+ n n -1)) 1) (A078898 (+ n n -1))))) ;; Code for A083221bi given in A083221.

%Y Inverse: A250471.

%Y Odd bisection of A250470. The other bisection: A250479.

%Y Cf. A055396, A064216, A078898, A083140, A083221, A114881, A114883.

%K nonn

%O 1,2

%A _Antti Karttunen_, Dec 06 2014