a(n) = ceiling(li(2*2^n) - li(2^n)) - (pi(2*2^n) - pi(2^n)) with li(x) the logarithmic integral and pi(x) the prime counting function.

A223853

a(n) = ceiling(li(2*2^n) - li(2^n)) - (pi(2*2^n) - pi(2^n)) with li(x) the logarithmic integral and pi(x) the prime counting function.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =1a(4) =2a(5) =2a(6) =2a(7) =1a(8) =3a(9) =4a(10) =1a(11) =7a(12) =1a(13) =13a(14) =10a(15) =4a(16) =25a(17) =-5a(18) =49a(19) =17a(20) =38a(21) =82a(22) =103a(23) =-55a(24) =245a(25) =290a(26) =105a(27) =621a(28) =-107a(29) =1219

External references