A086355 Fixed point if [nonzero-digit product]-function at initial-value=prime(n) is iterated.

2, 3, 5, 7, 1, 3, 7, 9, 6, 8, 3, 2, 4, 2, 6, 5, 2, 6, 8, 7, 2, 8, 8, 4, 8, 1, 3, 7, 9, 3, 4, 3, 2, 4, 8, 5, 5, 8, 8, 2, 8, 8, 9, 4, 8, 8, 2, 2, 6, 8, 8, 2, 8, 1, 7, 8, 8, 4, 4, 6, 6, 2, 2, 3, 9, 2, 9, 8, 6, 8, 2, 5, 2, 8, 4, 4, 2, 4, 4, 8, 8, 8, 2, 8, 8, 6, 6, 4, 8, 4, 6, 2, 6, 8, 8, 5, 2, 1, 3, 2, 4, 5, 9, 4, 5

Offset: 1

Author

Labos Elemer, Jul 21 2003

Keywords

• base
• nonn

Examples

			n=100, prime(100)=541, iteration list={541,20,2}, a(100)=2.
		

Links

• Michael De Vlieger, Table of n, a(n) for n = 1..10000

Crossrefs

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

Programs

Mathematica

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

Formula

a(n) = A051802(A000040(n)) = fixed-point of A051801(n-th prime).