A086357 Fixed point if [nonzero-digit-product]-function at initial-value=A002110(n)=n-th primorial is iterated.

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, 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, 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

Offset

1,1

Links

Table of n, a(n) for n=1..105.

Formula

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

Example

n=7, 7th-primorial=510510, iteration list={510510,25,10,1},
a(100)=2.

Mathematica

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}]

Crossrefs

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

Sequence in context: A251755 A128203 A144531 * A138054 A297927 A321873

Adjacent sequences: A086354 A086355 A086356 * A086358 A086359 A086360

Keyword

base,nonn

Author

Labos Elemer, Jul 21 2003

Status

approved