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A075270
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Sum of Lucas numbers and inverted Lucas numbers: a(n)=A000032(n)*A075193(n).
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1
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3, -2, 7, -3, 18, -7, 47, -18, 123, -47, 322, -123, 843, -322, 2207, -843, 5778, -2207, 15127, -5778, 39603, -15127, 103682, -39603, 271443, -103682, 710647, -271443, 1860498, -710647, 4870847, -1860498, 12752043, -4870847, 33385282, -12752043, 87403803, -33385282, 228826127, -87403803
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,1
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COMMENTS
| a(n)=(1+(-1)^n)L(n)+((-1)^n)L(n-1), L(n) Lucas numbers.
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FORMULA
| a(n)=3a(n-2)-a(n-4), a(0)=3, a(1)=-2, a(2)=7, a(3)=-3. Ogf (3-2x-2x^2+3x^3)/(1-3x^2+x^4).
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MATHEMATICA
| CoefficientList[Series[(3-2x-2x^2+3x^3)/(1-3x^2+x^4), {x, 0, 40}], x]
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CROSSREFS
| Cf. A000032, A075193.
Sequence in context: A071190 A057020 A165794 * A067872 A198501 A011772
Adjacent sequences: A075267 A075268 A075269 * A075271 A075272 A075273
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KEYWORD
| easy,sign
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AUTHOR
| Mario Catalani (mario.catalani(AT)unito.it), Sep 12 2002
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