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Pell numbers




Numbers that are similar to the Fibonacci numbers and are generated by the formula

An = 2An-1 + An-2.

The sequence runs: 1, 2, 5, 12, 29, 70, 169, 408, 985, 2378, 5741, 13860, 33461, 80782, 195025, 470832, ... The ratio of successive terms approaches 1 plus the square root of 2.


Related category

   • TYPES OF NUMBERS