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%I #10 Dec 07 2019 12:18:26
%S 1,5,3,9,7,13,11,21,17,15,43,45,29,19,41,25,23,59,39,27,35,33,31,85,
%T 37,61,51,53,47,81,79,49,55,121,83,75,57,73,77,67,65,63,71,69,125,89,
%U 87,123,105,107,95,101,163,93,91,99,97,349,243,103,169,109,233,115,119,171
%N Roots of squares generated in A221643. That is, S = i^2 XOR (i+1)^2; increment i; if S is a square then square root of S is appended to a(n). Initially i=0. XOR is the binary logical exclusive-or operator.
%C Conjecture: this is a permutation of odd numbers.
%C b(n) = (a(n)-1)/2 begins: 0, 2, 1, 4, 3, 6, 5, 10, 8, 7, 21, 22, 14, 9, 20, 12, 11, 29, 19, 13, 17.
%o (Python)
%o import math
%o for i in range(1<<16):
%o s = (i*i) ^ ((i+1)*(i+1))
%o r = int(math.sqrt(s));
%o if s == r*r:
%o print str(r)+',',
%Y Cf. A221643, A224515.
%K nonn,base,less
%O 1,2
%A _Alex Ratushnyak_, Apr 08 2013
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