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A052779
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Expansion of e.g.f.: (log(1-x))^6.
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3
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0, 0, 0, 0, 0, 0, 720, 15120, 231840, 3265920, 45556560, 649479600, 9604465200, 148370508000, 2402005525920, 40797624067200, 726963917097600, 13580328282393600, 265689107448756480, 5437099866285377280, 116229410301685651200, 2591985252922277184000, 60218914823672258142720
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OFFSET
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0,7
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COMMENTS
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Original name: a simple grammar.
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LINKS
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FORMULA
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E.g.f.: log(-1/(-1+x))^6.
Recurrence: {a(1)=0, a(0)=0, a(2)=0, a(4)=0, a(3)=0, a(5)=0, a(6)=720, (1+15*n^2+6*n+6*n^5+15*n^4+20*n^3+n^6)*a(n+1) + (-63-186*n-225*n^2-6*n^5-45*n^4-140*n^3)*a(n+2) + (540*n+120*n^3+375*n^2+15*n^4+301)*a(n+3) + (-390*n-20*n^3-350-150*n^2)*a(n+4) + (140+15*n^2+90*n)*a(n+5) + (-21-6*n)*a(n+6) + a(n+7)}.
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MAPLE
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spec := [S, {B=Cycle(Z), S=Prod(B, B, B, B, B, B)}, labeled]: seq(combstruct[count](spec, size=n), n=0..20);
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PROG
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(PARI) a(n) = {6!*stirling(n, 6, 1)*(-1)^n} \\ Andrew Howroyd, Jul 27 2020
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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encyclopedia(AT)pommard.inria.fr, Jan 25 2000
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EXTENSIONS
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Name changed and terms a(20) and beyond from Andrew Howroyd, Jul 27 2020
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STATUS
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approved
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