A331700 Binary XOR of squares of divisors of n.

1, 5, 8, 21, 24, 40, 48, 85, 89, 120, 120, 168, 168, 240, 240, 341, 288, 317, 360, 504, 384, 408, 528, 680, 617, 520, 640, 1008, 840, 816, 960, 1365, 1072, 1440, 1248, 1197, 1368, 1224, 1360, 2040, 1680, 1920, 1848, 1560, 1864, 2640, 2208, 2728, 2385, 3021

Offset

1,2

Links

Rémy Sigrist, Table of n, a(n) for n = 1..8192

Rémy Sigrist, Colored scatterplot of the first 2^18 terms (where the color is function of A007814(n))

Example

For n = 6:
- the divisors of 6 are 1, 2, 3 and 6,
- so a(6) = 1 XOR 4 XOR 9 XOR 36 = 40.

Mathematica

Table[BitXor@@(Divisors[n]^2), {n, 50}] (* Harvey P. Dale, May 03 2023 *)

Prog

(PARI) a(n) = my (s=0); fordiv (n, d, s=bitxor(s, d^2)); s
(Python)
from functools import reduce
from operator import xor
from sympy import divisors
def A331700(n): return reduce(xor, (d**2 for d in divisors(n, generator=True))) # Chai Wah Wu, Jul 01 2022

Crossrefs

Cf. A001157, A007814, A178910, A295901.

Sequence in context: A268195 A169705 A138810 * A105634 A294124 A120036

Adjacent sequences: A331697 A331698 A331699 * A331701 A331702 A331703

Keyword

nonn,base

Author

Rémy Sigrist, Jan 25 2020

Status

approved