a(n) is the smallest k such that psi(k) and phi(k) have same distinct prime factors when k is the product of n distinct primes (psi(k) = A001615(k) and phi(k) = A000010(k)), or 0 if no such k exists.

A291138

a(n) is the smallest k such that psi(k) and phi(k) have same distinct prime factors when k is the product of n distinct primes (psi(k) = A001615(k) and phi(k) = A000010(k)), or 0 if no such k exists.

Terms

    a(0) =3a(1) =14a(2) =42a(3) =210a(4) =3570a(5) =43890a(6) =746130a(7) =14804790a(8) =281291010a(9) =8720021310a(10) =278196808890

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