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A062113
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a(0)=1; a(1)=2; a(n)=a(n-1)+ a(n-2)*(3-(-1)^n)/2
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1
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1, 2, 3, 7, 10, 24, 34, 82, 116, 280, 396, 956, 1352, 3264, 4616, 11144, 15760, 38048, 53808, 129904, 183712, 443520, 627232, 1514272, 2141504, 5170048, 7311552, 17651648, 24963200, 60266496, 85229696, 205762688, 290992384, 702517760
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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COMMENTS
| A bistable recurrence.
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LINKS
| Harry J. Smith, Table of n, a(n) for n=0,...,200
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FORMULA
| a(n) = a(n-1) + a(n-2) * A000034(n). [Reinhard Zumkeller, Jan 21 2012]
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PROG
| (PARI) { for (n=0, 200, if (n>1, a=a1 + a2*(3 - (-1)^n)/2; a2=a1; a1=a, if (n==0, a=a2=1, a=a1=2)); write("b062113.txt", n, " ", a) ) } [From Harry J. Smith (hjsmithh(AT)sbcglobal.net), Aug 01 2009]
(Haskell)
a062113 n = a062113_list !! n
a062113_list = 1 : 2 : zipWith (+)
(tail a062113_list) (zipWith (*) a000034_list a062113_list)
-- Reinhard Zumkeller, Jan 21 2012
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CROSSREFS
| Cf. A007068, A062112.
Sequence in context: A095010 A047082 A079380 * A130968 A007748 A126617
Adjacent sequences: A062110 A062111 A062112 * A062114 A062115 A062116
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KEYWORD
| easy,nonn
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AUTHOR
| Olivier Gerard (olivier.gerard(AT)gmail.com), Jun 05 2001
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