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A334752 a(n) is the number immediately below n in a clockwise square spiral of the positive integers with the first step to the right.

%I A334752 #18 May 11 2020 15:16:24
%S A334752 4,3,14,15,16,5,6,1,2,11,12,13,32,33,34,35,36,17,18,19,20,7,8,9,10,27,
%T A334752 28,29,30,31,58,59,60,61,62,63,64,37,38,39,40,41,42,21,22,23,24,25,26,
%U A334752 51,52,53,54,55,56,57,92,93,94,95,96,97,98,99,100,65,66
%N A334752 a(n) is the number immediately below n in a clockwise square spiral of the positive integers with the first step to the right.
%C A334752 Equivalently the number immediately above n in a counterclockwise square spiral of the positive integers with the first step to the right.
%C A334752 This is a permutation of the positive integers. A334751 is the inverse permutation.
%H A334752 Peter Kagey, <a href="/A334752/b334752.txt">Table of n, a(n) for n = 1..10000</a>
%H A334752 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>
%e A334752 For n = 1, a(1) = 4 because 4 is immediately below 1 in the clockwise square spiral with first step to the right:
%e A334752   21--22--23--24--25--26
%e A334752   |                    |
%e A334752   20  7---8---9---10  27
%e A334752   |   |            |   |
%e A334752   19  6   1---2   11  28
%e A334752   |   |       |    |   |
%e A334752   18  5---4---3   12  29
%e A334752   |                |   |
%e A334752   17--16--15--14--13  30
%e A334752                        |
%e A334752   36--35--34--33--32--31
%Y A334752 Cf. A068225 (right), A068226 (left), A334751 (above).
%Y A334752 Cf. A174344 (x-coordinate), A268038 (y-coordinate).
%K A334752 nonn
%O A334752 1,1
%A A334752 _Peter Kagey_, May 10 2020