Number of primes <= n is equal to the sum of squarefree numbers from the smallest prime factor of n to the largest prime factor of n.

A074252

Number of primes <= n is equal to the sum of squarefree numbers from the smallest prime factor of n to the largest prime factor of n.

Terms

    a(0) =1a(1) =4a(2) =12a(3) =30a(4) =84a(5) =9150a(6) =47244a(7) =75360a(8) =177287a(9) =281868a(10) =705790a(11) =3043504a(12) =9669715a(13) =20139930a(14) =32043111a(15) =67447484a(16) =291217662a(17) =7544909388a(18) =8396469108a(19) =21425170627

External references