And here is the syslog:

usb 6-1: new full speed USB device using uhci_hcd and address 2
usb 6-1: configuration #1 chosen from 1 choice
hub 6-1:1.0: USB hub found
hub 6-1:1.0: 2 ports detected
usb 6-1.1: new low speed USB device using uhci_hcd and address 3
usb 6-1.1: configuration #1 chosen from 1 choice
input: Logitech USB Receiver as /devices/pci0000:00/0000:00:1d.0/usb6/6-1/6-1.1/6-1.1:1.0/input/input5
generic-usb 0003:046D:C703.0003: input,hidraw2: USB HID v1.10 Keyboard [Logitech USB Receiver] on usb-0000:00:1d.0-1.1/input0
input: Logitech USB Receiver as /devices/pci0000:00/0000:00:1d.0/usb6/6-1/6-1.1/6-1.1:1.1/input/input6
generic-usb 0003:046D:C703.0004: input,hiddev97,hidraw3: USB HID v1.10 Mouse [Logitech USB Receiver] on usb-0000:00:1d.0-1.1/input1
usb 6-1.2: new full speed USB device using uhci_hcd and address 4
usb 6-1.2: configuration #1 chosen from 1 choice
Bluetooth: Core ver 2.15
Bluetooth: HCI device and connection manager initialized
Bluetooth: HCI socket layer initialized
Bluetooth: Generic Bluetooth USB driver ver 0.6
usbcore: registered new interface driver btusb
input: Logitech MX900 Mouse as /devices/pci0000:00/0000:00:1d.0/usb6/6-1/6-1.2/6-1.2:1.0/bluetooth/hci0/hci0:44/input8
generic-bluetooth 0005:046D:B001.0005: input,hidraw4: BLUETOOTH HID v22.01 Mouse [Logitech MX900 Mouse] on 00:07:61:12:29:48
input: Logitech Elite Keyboard as /devices/pci0000:00/0000:00:1d.0/usb6/6-1/6-1.2/6-1.2:1.0/bluetooth/hci0/hci0:41/input9
generic-bluetooth 0005:046D:B301.0006: input,hidraw5: BLUETOOTH HID v23.04 Keyboard [Logitech Elite Keyboard] on 00:07:61:12:29:48

Now I disconnect the receiver

usb 6-1: USB disconnect, address 2
usb 6-1.1: USB disconnect, address 3
bluetoothd: HCI dev 0 down
bluetoothd: Adapter /org/bluez/1276/hci0 has been disabled
bluetoothd: Stopping security manager 0
usb 6-1.2: USB disconnect, address 4
bluetoothd: HCI dev 0 unregistered
bluetoothd: Unregister path: /org/bluez/1276/hci0

and reconnect it 

usb 6-1: new full speed USB device using uhci_hcd and address 5
usb 6-1: configuration #1 chosen from 1 choice
hub 6-1:1.0: USB hub found
hub 6-1:1.0: 2 ports detected
usb 6-1.1: new low speed USB device using uhci_hcd and address 6
usb 6-1.1: configuration #1 chosen from 1 choice
input: Logitech USB Receiver as /devices/pci0000:00/0000:00:1d.0/usb6/6-1/6-1.1/6-1.1:1.0/input/input12
generic-usb 0003:046D:C703.0009: input,hidraw2: USB HID v1.10 Keyboard [Logitech USB Receiver] on usb-0000:00:1d.0-1.1/input0
input: Logitech USB Receiver as /devices/pci0000:00/0000:00:1d.0/usb6/6-1/6-1.1/6-1.1:1.1/input/input13
generic-usb 0003:046D:C703.000A: input,hiddev97,hidraw3: USB HID v1.10 Mouse [Logitech USB Receiver] on usb-0000:00:1d.0-1.1/input1
usb 6-1: USB disconnect, address 5
usb 6-1.1: USB disconnect, address 6
usb 6-1: new full speed USB device using uhci_hcd and address 7
usb 6-1: configuration #1 chosen from 1 choice
hub 6-1:1.0: USB hub found
hub 6-1:1.0: 2 ports detected
usb 6-1.1: new low speed USB device using uhci_hcd and address 8
usb 6-1.1: configuration #1 chosen from 1 choice
input: Logitech USB Receiver as /devices/pci0000:00/0000:00:1d.0/usb6/6-1/6-1.1/6-1.1:1.0/input/input14
generic-usb 0003:046D:C703.000B: input,hidraw2: USB HID v1.10 Keyboard [Logitech USB Receiver] on usb-0000:00:1d.0-1.1/input0
input: Logitech USB Receiver as /devices/pci0000:00/0000:00:1d.0/usb6/6-1/6-1.1/6-1.1:1.1/input/input15
generic-usb 0003:046D:C703.000C: input,hiddev97,hidraw3: USB HID v1.10 Mouse [Logitech USB Receiver] on usb-0000:00:1d.0-1.1/input1