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Simple self-inverse permutation of natural numbers: List each block of n^2 - n + 1 numbers from ((n-1)^3 + 2*(n-1))/3 + 1 to (n^3 + 2*n)/3 in reverse order.
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%I #16 Jul 11 2013 15:41:16

%S 0,1,4,3,2,11,10,9,8,7,6,5,24,23,22,21,20,19,18,17,16,15,14,13,12,45,

%T 44,43,42,41,40,39,38,37,36,35,34,33,32,31,30,29,28,27,26,25,76,75,74,

%U 73,72,71,70,69,68,67,66,65,64,63,62,61,60,59,58,57,56,55,54,53,52,51,50,49,48,47,46

%N Simple self-inverse permutation of natural numbers: List each block of n^2 - n + 1 numbers from ((n-1)^3 + 2*(n-1))/3 + 1 to (n^3 + 2*n)/3 in reverse order.

%C In other words, after zero, list each block of A002061(n) numbers from A116731(n) to A006527(n) in reverse order.

%H Antti Karttunen, <a href="/A227182/b227182.txt">Table of n, a(n) for n = 0..9951</a>

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

%F a(n) = A006527(A227177(n)) - A227179(n).

%t Flatten[(Reverse/@( (-1+#) (9-5 #+#^2)/3+Range[(#-2) (#-1)+1]-1)&)[Range[7]]] (* _Peter J. C. Moses_, Jul 11 2013 *)

%o (Scheme): (define (A227182 n) (- (A006527 (A227177 n)) (A227179 n)))

%Y Cf. A227177, A227179, A227147.

%K nonn

%O 0,3

%A _Antti Karttunen_, Jul 04 2013