Definition:Fermat Number/Sequence

Sequence of Fermat Numbers
The sequence of Fermat numbers begins:
 * $3, 5, 17, 257, 65 \, 537, 4 \, 294 \, 967 \, 297, 18 \, 446 \, 744 \, 073 \, 709 \, 551 \, 617, \ldots$