A090080 In binary expansion of n-th prime: reduce contiguous blocks of 0's to 0 and contiguous blocks of 1's to 1.

2, 1, 5, 1, 5, 5, 5, 5, 5, 5, 1, 21, 21, 21, 5, 21, 5, 5, 5, 5, 21, 5, 21, 21, 5, 21, 5, 21, 21, 5, 1, 5, 21, 21, 85, 21, 21, 21, 21, 85, 21, 85, 5, 5, 21, 5, 21, 5, 5, 21, 21, 5, 5, 5, 5, 5, 21, 5, 85, 21, 21, 85, 21, 21, 21, 21, 85, 85, 85, 85, 21, 21, 21, 85, 21, 5, 21, 21, 21

Offset: 1

Author

Reinhard Zumkeller, Nov 20 2003

Keywords

• nonn
• base

Comments

a(n) = A090079(A000040(n)).

Examples

			A000040(25)=97 -> '1100001' -> [11][0000][1] -> [1][0][1] ->
'101' -> 5=a(25).
		

Crossrefs

Cf. A004676.