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Search: id:A159695
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| A159695 |
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a(0)=7, a(n)=2*a(n-1)+2^(n-1) for n>0 . |
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+0
5
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| 7, 15, 32, 68, 144, 304, 640, 1344, 2816, 5888, 12288, 25600, 53248, 110592, 229376, 475136, 983040, 2031616, 4194304, 8650752, 17825792, 36700160, 75497472, 155189248, 318767104, 654311424, 1342177280, 2751463424, 5637144576
(list; graph; listen)
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OFFSET
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0,1
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COMMENT
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Diagonal of triangles A062111, A152920 .
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FORMULA
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a(n)=Sum_{k=0..n} (k+7)*binomial(n,k).
a(n) = (14+n)*2^(n-1) = 4*a(n-1)-4*a(n-2). G.f.: (7-13x)/(1-2x)^2. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Apr 20 2009]
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EXAMPLE
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a(0)=7, a(1)=2*7+1=15, a(2)=2*15+2=32, a(3)=2*32+4=68, a(4)=2*68+8=144, ...
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CROSSREFS
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Cf. A000079, A001787, A001792, A045623, A045891, A034007, A111297, A159694
Sequence in context: A137196 A120094 A078485 this_sequence A014001 A063592 A159792
Adjacent sequences: A159692 A159693 A159694 this_sequence A159696 A159697 A159698
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KEYWORD
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easy,nonn
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AUTHOR
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Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Apr 20 2009
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EXTENSIONS
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More terms from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Apr 20 2009
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