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A145027
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a(n)=a(n-1)+a(n-2)+a(n-3) with a(1) = 2, a(2) = 3, a(3) = 4.
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1
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2, 3, 4, 9, 16, 29, 54, 99, 182, 335, 616, 1133, 2084, 3833, 7050, 12967, 23850, 43867, 80684, 148401, 272952, 502037, 923390, 1698379, 3123806, 5745575, 10567760, 19437141, 35750476, 65755377, 120942994, 222448847, 409147218, 752539059
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| If the conjectured recurrence in A000382 is correct, then a(n) = A000382(n+2)-A000382(n+1), n>=4. - R. J. Mathar, Jan 30 2011
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FORMULA
| a(n) = -A000073(n-1)+A000073(n)+2*A000073(n+1). G.f. (1+x)*(x-2)*x / ( -1+x+x^2+x^3 ). - R. J. Mathar, Jan 30 2011
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MATHEMATICA
| a=2; b=3; c=4; lst={a, b, c}; Do[d=a+b+c; AppendTo[lst, d]; a=b; b=c; c=d, {n, 5!}]; lst
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CROSSREFS
| Cf. A000073, A000213, A001590, A003265, A056816, A081172, A001644.
Sequence in context: A192818 A119721 A098969 * A088275 A014281 A086865
Adjacent sequences: A145024 A145025 A145026 * A145028 A145029 A145030
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KEYWORD
| nonn
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AUTHOR
| Vladimir Orlovsky (4vladimir(AT)gmail.com), Sep 30 2008
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