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A152174
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a(n) = -2*a(n-1)+4*a(n-2), n>1 ; a(0) = 1, a(1) = -4.
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5
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1, -4, 12, -40, 128, -416, 1344, -4352, 14080, -45568, 147456, -477184, 1544192, -4997120, 16171008, -52330496, 169345024, -548012032, 1773404160, -5738856448, 18571329536, -60098084864, 194481487872, -629355315200
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OFFSET
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0,2
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COMMENTS
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LINKS
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FORMULA
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G.f.: (1-2x)/(1+2x-4x^2).
a(n) = Sum_{k=0..n} A147703(n,k)*(-5)^k.
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MATHEMATICA
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LinearRecurrence[{-2, 4}, {1, -4}, 30] (* Harvey P. Dale, Feb 13 2023 *)
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PROG
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CROSSREFS
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KEYWORD
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sign,easy,changed
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AUTHOR
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STATUS
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approved
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