1,2

Robert Israel, Table of n, a(n) for n = 1..10000

Obtained by removing all even numbers from A000720. Block lengths (frequencies of repetitions) are in A078584.

seq((2*n-1)$(ithprime(2*n)-ithprime(2*n-1)), n=1..30); # Robert Israel, Feb 13 2019

Select[PrimePi[Range[300]], OddQ] (* Harvey P. Dale, Dec 24 2014 *)

Cf. A000720, A005408.

Sequence in context: A088524 A129337 A133909 * A206913 A117767 A293701

Adjacent sequences: A177688 A177689 A177690 * A177692 A177693 A177694

nonn,easy

Giovanni Teofilatto, May 11 2010

Erroneous formula removed by R. J. Mathar, May 14 2010

approved