a(n) is the denominator of the sum of reciprocals of primes not exceeding n and not dividing binomial(2*n, n).

A334075

a(n) is the denominator of the sum of reciprocals of primes not exceeding n and not dividing binomial(2*n, n).

Terms

    a(0) =1a(1) =1a(2) =3a(3) =3a(4) =5a(5) =5a(6) =35a(7) =7a(8) =21a(9) =105a(10) =55a(11) =165a(12) =429a(13) =1001a(14) =1001a(15) =1001a(16) =1547a(17) =221a(18) =4199a(19) =323a(20) =2261a(21) =24871a(22) =572033a(23) =572033a(24) =408595a(25) =312455a(26) =937365a(27) =17043a(28) =8671a(29) =130065

External references