Musnad Ahmad 1012:99

Haywah ibn Shurayh narrated to us, Baqiyyah narrated to us, Buhayr ibn Sa’d narrated to me, from Khalid ibn Ma’dan, from ‘Ubadah ibn al-Samit, that the Messenger of Allah (peace and blessings of Allah be upon him) said: "Laylat al-Qadr is in the remaining ten nights. Whoever stands in them seeking their reward, Allah will forgive him his past and future sins. It is an odd night: the ninth, the seventh, the fifth, the third, or the last night." And the Messenger of Allah (peace and blessings of Allah be upon him) said: "The sign of Laylat al-Qadr is that it is clear and bright, as if there is a radiant moon in it; it is still and calm, with no cold or heat in it. It is not permitted for a star to be thrown in it until morning. And its sign is that the sun rises on its morning level, having no rays, like the moon on the night of the full moon. It is not permitted for the devil to emerge with it on that day."