cp's OEIS Frontend

A379348 Number of positive integers of the form k^2 - 2 whose greatest prime factor is A038873(n), the n-th prime not congruent to 3 or 5 mod 8.

%I A379348 #6 Dec 22 2024 23:56:28
%S A379348 1,3,4,6,5,8,10,10,10,14,20,22,30,30,37,42,43,48,49,64,80
%N A379348 Number of positive integers of the form k^2 - 2 whose greatest prime factor is A038873(n), the n-th prime not congruent to 3 or 5 mod 8.
%C A379348 See A242488 for additional information.
%H A379348 Filip Najman, <a href="http://web.math.hr/~fnajman/smooth.pdf">Smooth values of some quadratic polynomials</a>, Glasnik Matematicki Series III 45 (2010), pp. 347-355.
%e A379348 Table showing n, p = A038873(n) and a(n):
%e A379348    1    2    1
%e A379348    2    7    3
%e A379348    3   17    4
%e A379348    4   23    6
%e A379348    5   31    5
%e A379348    6   41    8
%e A379348    7   47   10
%e A379348    8   71   10
%e A379348    9   73   10
%e A379348   10   79   14
%e A379348   ...
%Y A379348 Row lengths of A242488.
%Y A379348 Cf. A038873, A185396, A379349.
%K A379348 nonn,more
%O A379348 1,2
%A A379348 _Andrew Howroyd_, Dec 22 2024