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%I #9 Mar 18 2022 21:53:23
%S 0,2,5,1,4,8,3,7,12,9,14,20,13,19,26,18,25,33,27,35,44,34,43,53,42,52,
%T 63,6,11,17,10,16,23,15,22,30,24,32,41,31,40,50,39,49,60,51,62,74,61,
%U 73,86,72,85,99,21,29,38,28,37,47,36,46,57,48,59,71,58,70,83,69,82,96
%N Inverse permutation to A163330.
%H A. Karttunen, <a href="/A163331/b163331.txt">Table of n, a(n) for n = 0..6560</a>
%H <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>
%F a(n) = A001477bi(A163326(n),A163325(n)), where A001477bi(x,y) = (((x+y)^2)+x+(3y))/2.
%o (Scheme:) (define (A163331 n) (A001477bi (A163326 n) (A163325 n)))
%o (define (A001477bi x y) (/ (+ (expt (+ x y) 2) x (* 3 y)) 2))
%Y Inverse: A163330. a(n) = A163329(A163327(n)). Cf. A007089.
%K nonn,base
%O 0,2
%A _Antti Karttunen_, Jul 29 2009