A086925 a(1) = 1; a(n+1) = a(n)/spf(a(n)) + number of earlier occurrences of a(n), spf=A020639 = smallest prime factor.

1, 2, 3, 3, 4, 3, 4, 4, 6, 4, 6, 5, 2, 3, 5, 3, 6, 6, 8, 5, 4, 7, 2, 4, 8, 6, 8, 7, 3, 7, 5, 5, 6, 10, 6, 10, 7, 5, 7, 7, 7, 8, 8, 9, 4, 9, 5, 8, 10, 8, 11, 2, 5, 9, 6, 11, 3, 8, 12, 7, 9, 7, 10, 9, 8, 13, 2, 6, 12, 8, 14, 8, 15, 6, 13, 3, 9, 9, 10, 10, 11, 4, 10, 12, 9, 11, 5, 10, 13, 4, 11, 6

Offset

1,2

Links

Table of n, a(n) for n=1..92.

Example

n=11: a(10) = 4 and a(9) = a(6) = 4, therefore a(11) =
a(10)/spf(a(10))+3 = 4/spf(4)+3 = 2+3 = 5.

Crossrefs

Sequence in context: A213251 A049108 A179846 * A088858 A372627 A113312

Adjacent sequences: A086922 A086923 A086924 * A086926 A086927 A086928

Keyword

nonn

Author

Reinhard Zumkeller, Sep 20 2003

Status

approved