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a(n) = floor( Gamma(n+3/7)/Gamma(3/7) ).
7

%I #12 Sep 08 2022 08:44:44

%S 1,0,0,1,5,22,122,787,5852,49330,465112,4850460,55433829,688963306,

%T 9251792972,133490155743,2059562402902,33835668047686,589707357402530,

%U 10867464157846629,211139303638163096,4313274345751046120

%N a(n) = floor( Gamma(n+3/7)/Gamma(3/7) ).

%H G. C. Greubel, <a href="/A020077/b020077.txt">Table of n, a(n) for n = 0..445</a>

%p Digits := 64:f := proc(n,x) trunc(GAMMA(n+x)/GAMMA(x)); end;

%p seq(floor(pochhammer(3/7,n)), n = 0..25); # _G. C. Greubel_, Nov 17 2019

%t Floor[Pochhammer[3/7, Range[0, 25]]] (* _G. C. Greubel_, Nov 17 2019 *)

%o (PARI) vector(26, n, my(x=3/7); gamma(n-1+x)\gamma(x) ) \\ _G. C. Greubel_, Nov 17 2019

%o (Magma) [Floor(Gamma(n+3/7)/Gamma(3/7)): n in [0..25]]; // _G. C. Greubel_, Nov 17 2019

%o (Sage) [floor(rising_factorial(3/7, n)) for n in (0..25)] # _G. C. Greubel_, Nov 17 2019

%Y Cf. A220608.

%Y Cf. A020074, A020075, A020076, A020078, A020079.

%K nonn

%O 0,5

%A _Simon Plouffe_