A394893 - OEIS

A394893

Number of integers x in range A002110(n-1) .. A002110(n)-1 such that the u-th arithmetic derivative of A276086(x) is zero for some u, and A328114(x) = prime(n-1), where A002110(n) is the n-th primorial, and A328114 gives the largest digit in the primorial base.

%I #6 Apr 13 2026 15:18:30

%S 1,2,1,4,5,23,76,554

%N Number of integers x in range A002110(n-1) .. A002110(n)-1 such that the u-th arithmetic derivative of A276086(x) is zero for some u, and A328114(x) = prime(n-1), where A002110(n) is the n-th primorial, and A328114 gives the largest digit in the primorial base.

%C Question: What is the eventual growth rate of this sequence?

%C Computing the term a(9) would be require almost as much resources as computing of the term A351071(8). See further comments in that sequence.

%o (PARI) A394893(n) = A394890_sq(n,prime(n)-1);

%Y Right edge of triangle A394890.

%Y Cf. A002110, A003415, A276086, A328114, A328116, A351071.

%K nonn,hard,more

%O 1,2

%A _Antti Karttunen_, Apr 07 2026