%I #9 Dec 06 2015 21:13:06
%S 0,1,2,3,8,5,6,7,4,9,10,17,24,26,14,15,23,11,18,29,20,21,25,16,12,22,
%T 13,27,28,19,30,71,44,51,62,35,72,89,53,78,80,41,42,68,32,45,86,59,69,
%U 77,50,33,65,38,54,83,56,87,74,47,60,61,34,63,88,52,75,79,43,48,70,31,36,85,58,66,76,49,39,67,40,81
%N Self-inverse permutation of nonnegative integers: a(n) = A263273(8*n)/8.
%C Note that n=13 is the first point where this involution does not preserve the parity as a(13) = 26.
%H Antti Karttunen, <a href="/A264978/b264978.txt">Table of n, a(n) for n = 0..7381</a>
%H <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>
%F a(n) = A263273(8*n)/8.
%F a(n) = A263272(4*n)/4.
%F a(n) = A264974(2*n)/2.
%F Other identities. For all n >= 0:
%F a(3*n) = 3*a(n).
%o (Scheme, three different variants)
%o (define (A264978 n) (/ (A263273 (* 8 n)) 8))
%o (define (A264978 n) (/ (A263272 (* 4 n)) 4))
%o (define (A264978 n) (/ (A264974 (* 2 n)) 2))
%Y Cf. A263273, A263272, A264974.
%K nonn
%O 0,3
%A _Antti Karttunen_, Dec 06 2015