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[r]*[2r]*[3r]*...[nr], where r=(1+sqrt(5))/2 and []=floor.
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%I #12 Aug 19 2024 12:53:15

%S 1,3,12,72,576,5184,57024,684288,9580032,153280512,2605768704,

%T 49509605376,1039701712896,22873437683712,548962504409088,

%U 13724062610227200,370549690476134400,10745941023807897600,322378230714236928000,10316103382855581696000,340431411634234195968000,11915099407198196858880000,440858678066333283778560000,16752629766520664783585280000,670105190660826591343411200000

%N [r]*[2r]*[3r]*...[nr], where r=(1+sqrt(5))/2 and []=floor.

%F a(n)=[r]*[2r]*[3r]*...[nr], where r=(1+sqrt(5))/2 and []=floor.

%F a(n) ~ c * r^n * n! / n^(1/(2*r)), where c = 0.7044932... and r = A001622 is the golden ratio. - _Vaclav Kotesovec_, Aug 19 2024

%e a(n)=1*3*12*72*...*floor(r*n), where r = golden ratio.

%t a[n_]:=Floor[n*(1+5^(1/2))/2];

%t f[n_]:=Product[a[i],{i,n}];

%t Table[f[n],{n,1,25}]

%Y Cf. A000201 (lower Wythoff sequence).

%K nonn

%O 1,2

%A _Clark Kimberling_, Jan 22 2011