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A112498
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Third column of second-order Eulerian triangle A008517 divided by 2.
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1
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3, 29, 164, 726, 2805, 9975, 33630, 109424, 347519, 1085313, 3349848, 10253994, 31203945, 94561643, 285716018, 861472836, 2593592883, 7800176565, 23441423340, 70410252350, 211411111133, 634610819679, 1904620987014
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OFFSET
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3,1
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COMMENTS
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See A004301 for the doubled sequence.
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LINKS
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FORMULA
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G.f.: x^3*(3-x-6*x^2)/(((1-x)^3)*((1-2*x)^2)*(1-3*x)). See the comment on column g.f.s under A008517.
a(n) = 3*a(n-1) + (2*n-3)*(2^(n-1)-n), n>3, with a(3)=3.
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CROSSREFS
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Cf. A000295 (one half of second column).
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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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