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%I #16 May 03 2023 16:15:54
%S 1,5,8,21,24,40,48,85,89,120,120,168,168,240,240,341,288,317,360,504,
%T 384,408,528,680,617,520,640,1008,840,816,960,1365,1072,1440,1248,
%U 1197,1368,1224,1360,2040,1680,1920,1848,1560,1864,2640,2208,2728,2385,3021
%N Binary XOR of squares of divisors of n.
%H Rémy Sigrist, <a href="/A331700/b331700.txt">Table of n, a(n) for n = 1..8192</a>
%H Rémy Sigrist, <a href="/A331700/a331700.png">Colored scatterplot of the first 2^18 terms</a> (where the color is function of A007814(n))
%e For n = 6:
%e - the divisors of 6 are 1, 2, 3 and 6,
%e - so a(6) = 1 XOR 4 XOR 9 XOR 36 = 40.
%t Table[BitXor@@(Divisors[n]^2),{n,50}] (* _Harvey P. Dale_, May 03 2023 *)
%o (PARI) a(n) = my (s=0); fordiv (n, d, s=bitxor(s, d^2)); s
%o (Python)
%o from functools import reduce
%o from operator import xor
%o from sympy import divisors
%o def A331700(n): return reduce(xor,(d**2 for d in divisors(n,generator=True))) # _Chai Wah Wu_, Jul 01 2022
%Y Cf. A001157, A007814, A178910, A295901.
%K nonn,base
%O 1,2
%A _Rémy Sigrist_, Jan 25 2020
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