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Rearrangement of positive integers: parity of a[n] is opposite to parity of n-th digit of decimal expansion of Pi (see comments).
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%I #5 Oct 01 2016 16:51:36

%S 2,4,1,6,8,3,10,12,14,5,7,16,18,20,9,22,24,26,28,11,30,13,15,17,19,21,

%T 23,32,34,25,36,27,38,40,42,29,31,33,35,37,44,46,48,50,39,52,54,56,58,

%U 60,62,64,66,41,68,43,45,47,70,72,49,74,51,53,76,78,55,80,57,82,59,84

%N Rearrangement of positive integers: parity of a[n] is opposite to parity of n-th digit of decimal expansion of Pi (see comments).

%C Take decimal expansion of pi: 3,1,4,1,5,9,2,6,5,... First digit pi(1)=3, hence a(1)=2; pi(2)=1, hence a(2)=4, pi(3)=4, hence a(3)=1, etc.

%Y Cf. A105353 - A105360.

%K nonn,base

%O 1,1

%A _Zak Seidov_, Apr 01 2005