login
A090000
Length of longest contiguous block of 1's in binary expansion of n-th prime.
6
1, 2, 1, 3, 2, 2, 1, 2, 3, 3, 5, 1, 1, 2, 4, 2, 3, 4, 2, 3, 1, 4, 2, 2, 2, 2, 3, 2, 2, 3, 7, 2, 1, 2, 1, 3, 3, 2, 3, 2, 2, 2, 6, 2, 2, 3, 2, 5, 3, 3, 3, 4, 4, 5, 1, 3, 2, 4, 1, 2, 2, 1, 2, 3, 3, 4, 2, 1, 2, 3, 2, 3, 4, 3, 4, 7, 2, 2, 2, 2, 2, 2, 4, 2, 3, 3, 3, 3, 3, 4, 3, 5, 4, 4, 5, 5, 7, 1, 2, 3, 2, 2, 2, 3, 3
OFFSET
1,2
COMMENTS
a(n) = A038374(A000040(n)).
MATHEMATICA
f[n_] := Length[ Union[ DeleteCases[ Split[ IntegerDigits[n, 2]], 0, 2]][[ -1]]]; Table[ f[ Prime[n]], {n, 1, 105}] (* Robert G. Wilson v, Dec 04 2003 *)
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Nov 20 2003
STATUS
approved