| 释义 | 
		Jacobsthal NumberThe Jacobsthal numbers are the numbers obtained by the  s in the Lucas Sequence with   and  ,corresponding to   and  . They and the Jacobsthal-Lucas numbers (the  s) satisfy the Recurrence Relation
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  The Jacobsthal numbers satisfy   and   and are 0, 1, 1, 3, 5, 11, 21, 43, 85, 171, 341, ... (Sloane's A001045).The Jacobsthal-Lucas numbers satisfy   and   and are 2, 1, 5, 7, 17, 31, 65, 127, 257, 511, 1025, ...(Sloane's A014551).  The properties of these numbers are summarized in Horadam (1996).  They are given by the closed formexpressions
  where   is the Floor Function and   is a Binomial Coefficient.  The Binet forms are
 
 
 
 The Generating Functions are
    | (6) |  
 
   | (7) |  
  The Simson Formulas are
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  Summation Formulas include
  Interrelationships are
   | (12) |  
 
   | (13) |  
 
   | (14) |  
 
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   | (16) |  
 
   | (17) |  
 
   | (18) |  
 
 
 
   | (21) |  
 
   | (22) |  
 
   | (23) |  
 
   | (24) |  
 
   | (25) |  
 
   | (26) |  
 
   | (27) |  
 
   | (28) |  
 
   | (29) |  
 
   | (30) |  
 
   | (31) |  
  (Horadam 1996). References
 Horadam, A. F.  ``Jacobsthal and Pell Curves.''  Fib. Quart. 26, 79-83, 1988.Horadam, A. F.  ``Jacobsthal Representation Numbers.''  Fib. Quart. 34, 40-54, 1996. Sloane, N. J. A.  SequencesA014551 andA001045/M2482in ``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.   |