a(n) = floor(1/(1-s(n))) where s(n) = Sum_{k=1..n} phi(k)/k * log(2^k/(2^k-1)). phi(k) is the Euler totient function A000010(k).
A383024
a(n) = floor(1/(1-s(n))) where s(n) = Sum_{k=1..n} phi(k)/k * log(2^k/(2^k-1)). phi(k) is the Euler totient function A000010(k).
Terms
- a(0) =3a(1) =6a(2) =13a(3) =23a(4) =61a(5) =90a(6) =229a(7) =417a(8) =917a(9) =1429a(10) =3916a(11) =5748a(12) =16323a(13) =28489a(14) =53121a(15) =89322a(16) =249079a(17) =364536a(18) =1068096a(19) =1802530a(20) =3542367a(21) =5749605a(22) =16694858a(23) =24980973a(24) =61771834a(25) =107398135a(26) =230197552a(27) =363961698a(28) =1053601058a(29) =1426995284
External references
- oeis: A383024