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Fixed point if [nonzero-digit-product]-function at initial-value=A002110(n)=n-th primorial is iterated.
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%I #6 Oct 15 2013 22:32:15

%S 2,6,3,2,6,9,1,6,8,2,8,8,8,8,6,8,6,7,8,2,8,8,8,6,2,8,1,6,8,2,2,2,8,6,

%T 8,8,8,6,4,6,2,8,2,6,6,2,2,2,6,6,8,6,2,8,8,8,5,8,6,8,2,8,8,1,2,2,8,6,

%U 8,2,2,8,2,8,8,2,2,8,8,9,6,8,4,6,8,8,8,2,8,6,8,1,6,2,2,8,1,6,6,8,6,9,2,6,2

%N Fixed point if [nonzero-digit-product]-function at initial-value=A002110(n)=n-th primorial is iterated.

%F a(n)=A051802[A002110(n)]=fixed-point of A051801[A002110(n)]

%e n=7, 7th-primorial=510510, iteration list={510510,25,10,1},

%e a(100)=2.

%t prd[x_] := Apply[Times, DeleteCases[IntegerDigits[x], 0]] q[x_] := Apply[Times, Table[Prime[w], {w, 1, x}]] Table[FixedPoint[prd, q[w]], {w, 1, 128}]

%Y Cf. A051801, A051802, A086353-A086361, A029898, A010888, A038194, A000984.

%K base,nonn

%O 1,1

%A _Labos Elemer_, Jul 21 2003