A090207 Number of factors of n-th nonprime Fibonacci number.

1, 1, 1, 3, 2, 2, 2, 6, 2, 3, 3, 5, 2, 4, 3, 2, 9, 3, 2, 4, 4, 7, 2, 4, 3, 2, 3, 10, 3, 3

Offset

0,4

Links

Table of n, a(n) for n=0..29.

Formula

F(0) = 0; F(1) = 1; F(n) = F(n-1) + F(n-2); F(0:9) = 0, 1, 1, 2, 3, 5, 8, 13, 21, 34 The nonprime numbers are: 0, 1, 1, 8, 21, 34 which have number of factors: 1, 1, 1, 3, 2, 2

Crossrefs

Cf. A090206, A000045.

Sequence in context: A175333 A130845 A134653 * A364571 A202538 A239736

Adjacent sequences: A090204 A090205 A090206 * A090208 A090209 A090210

Keyword

easy,nonn

Author

Felix Tubiana, Jan 22 2004

Status

approved