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A098293
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Powers of 2 alternating with powers of 3.
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2
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1, 1, 2, 3, 4, 9, 8, 27, 16, 81, 32, 243, 64, 729, 128, 2187, 256, 6561, 512, 19683, 1024, 59049, 2048, 177147, 4096, 531441, 8192, 1594323, 16384, 4782969, 32768, 14348907, 65536, 43046721, 131072, 129140163, 262144, 387420489, 524288
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OFFSET
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0,3
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COMMENTS
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The finite sequence [1,2,3,4,9,8,27] is used in Timaios [35b] by Platon.
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REFERENCES
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Luc Brisson, Le Même et l'Autre dans la Structure Ontologique du Timée de Platon, Klincksieck, Paris, 1974, p. 317.
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LINKS
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FORMULA
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a(2*k) = 2^k, a(2*k+1) = 3^k, k>=0.
G.f.: (1+x-3*x^2-2*x^3)/((1-2*x^2)*(1-3*x^2)).
a(n) = ((5-(-1)^n)/2)^((2*n-1+(-1)^n)/4). - Luce ETIENNE, Dec 13 2014
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MAPLE
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MATHEMATICA
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With[{nn=20}, Riffle[2^Range[0, nn], 3^Range[0, nn]]] (* Harvey P. Dale, Nov 28 2011 *)
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PROG
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CROSSREFS
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Except for initial 1, reordering of A006899.
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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