A034170 - OEIS

%I #13 Aug 04 2020 01:53:38

%S 5,13,21,33,37,57,85,93,105,133,165,177,253,273,345,357,385,1365

%N Disjoint discriminants (one form per genus) of type 1.

%C A subsequence of A000926, A139826, and A232528. - _Andrew Howroyd_, Jun 09 2018

%D L. E. Dickson, Introduction to the theory of numbers, Dover, NY, 1929.

%D J. M. Borwein and P. B. Borwein, Pi and the AGM, page 293.

%F Intersection of A004766 and A139826. - _Andrew Howroyd_, Jun 09 2018

%o (PARI) ok(n)={n<>1 && n%4==1 && issquarefree(n) && !select(t->t<>2, quadclassunit(-4*n).cyc)} \\ _Andrew Howroyd_, Jun 09 2018

%Y Cf. A000926, A004766, A034169, A139826, A232528.

%K nonn,fini,full

%O 1,1

%A Jonathan Borwein (jborwein(AT)cecm.sfu.ca), Stephen Choi (choi(AT)cecm.sfu.ca)