释义 |
Fibonacci n-Step NumberAn -step Fibonacci sequence is given by defining for , , , and
 | (1) |
for . The case corresponds to the degenerate 1, 1, 2, 2, 2, 2 ..., to the usual FibonacciNumbers 1, 1, 2, 3, 5, 8, ... (Sloane's A000045), to the A000073), to the Tetranacci Numbers1, 1, 2, 4, 8, 15, 29, 56, 108, ... (Sloane's A000078), etc.
The limit is given by solving
 | (2) |
for and taking the Real Root . If , the equation reduces to
 | (3) |
 | (4) |
giving solutions
 | (5) |
The ratio is therefore
 | (6) |
which is the Golden Ratio, as expected.Solutions for , 2, ... are given numerically by 1, 1.61803, 1.83929, 1.92756, 1.96595, ..., approaching 2 as .See also Fibonacci Number, Tribonacci Number References
Sloane, N. J. A. SequencesA000045/M0692,A000073/M1074, andA000078/M1108in ``An On-Line Version of the Encyclopedia of Integer Sequences.''http://www.research.att.com/~njas/sequences/eisonline.html and Sloane, N. J. A. and Plouffe, S.The Encyclopedia of Integer Sequences. San Diego: Academic Press, 1995.
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