cp's OEIS Frontend

A379349 Number of integers of the form k^2 + 2 whose greatest prime factor is A033203(n), the n-th prime not congruent to 5 or 7 mod 8.

%I A379349 #5 Dec 22 2024 23:56:19
%S A379349 1,5,5,7,11,12,18,18,21,25,30,47,39,45,62,63,83,81,107,105,130
%N A379349 Number of integers of the form k^2 + 2 whose greatest prime factor is A033203(n), the n-th prime not congruent to 5 or 7 mod 8.
%C A379349 See A379350 for additional information.
%H A379349 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 A379349 Table showing n, p = A033203(n) and a(n):
%e A379349    1    2    1
%e A379349    2    3    5
%e A379349    3   11    5
%e A379349    4   17    7
%e A379349    5   19   11
%e A379349    6   41   12
%e A379349    7   43   18
%e A379349    8   59   18
%e A379349    9   67   21
%e A379349   10   73   25
%e A379349   ...
%Y A379349 Row lengths of A379350.
%Y A379349 Cf. A033203, A181471, A379346, A379348.
%K A379349 nonn,more
%O A379349 1,2
%A A379349 _Andrew Howroyd_, Dec 22 2024