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Search: id:A121311
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| A121311 |
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a(0) = 1, a(1) = 2, a(2) = 5; for n >= 3, a(n) = a(n - 1) - 2*a(n - 2) + a(n - 3). |
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+0
1
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| 1, 2, 5, 2, -6, -5, 9, 13, -10, -27, 6, 50, 11, -83, -55, 122, 149, -150, -326, 123, 625, 53, -1074, -555, 1646, 1682, -2165, -3883, 2129, 7730, -411, -13742, -5190, 21883, 18521, -30435, -45594, 33797, 94550, -18638, -173941, -42115, 287129, 197418, -418955, -526662, 508666, 1143035, -400959
(list; graph; listen)
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OFFSET
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1,2
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FORMULA
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O.g.f.: -x*(1+x+5*x^2)/(-1+x-2*x^2+x^3) . - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Dec 10 2007
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MATHEMATICA
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a[0] = 1; a[1] = 2; a[2] = 5; a[n_] := a[n] = a[n - 1] - 2a[n - 2] + a[n - 3]; Table[ a[n], {n, 0, 40}]
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CROSSREFS
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Cf. A101399.
Sequence in context: A107060 A016589 A089122 this_sequence A067948 A086956 A016580
Adjacent sequences: A121308 A121309 A121310 this_sequence A121312 A121313 A121314
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KEYWORD
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sign
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AUTHOR
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Zak Seidov (zakseidov(AT)yahoo.com), Aug 25 2006
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