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A182600
Run length of the n-th run of Fibonacci composites.
1
1, 3, 1, 3, 5, 5, 13, 3, 35, 47, 5, 221, 71, 1, 15, 59, 59, 1, 2399, 1751, 663, 3923, 365, 4753, 11129, 5195, 5241, 1511, 13321, 31005, 23071, 25109, 18069, 53015, 196271, 36401, 156259, 3647, 11021, 326805, 118379, 235709, 350399, 167051, 165661, 935631
OFFSET
1,2
COMMENTS
There is no upper bound to the entries: F_{k*n} is divisible by F_k, so whenever integers j, j+1, ..., j+n are composite (and > 4), F_j, ..., F_{j+n} are also composite. - Robert Israel, Nov 19 2010
FORMULA
a(n) = A001605(n+3)-A001605(n+2)-1.
EXAMPLE
The first run contains A000045(6), the second A000045(8..10), the third A000045(12), the fourth A000045(14..16).
CROSSREFS
Sequence in context: A016646 A345943 A342342 * A371928 A179760 A334852
KEYWORD
nonn
AUTHOR
R. J. Mathar, Nov 22 2010
STATUS
approved