1,3

Number of quadratic polynomials with coefficients from {1..n} for which both roots are integers.

A generalization of A006318.

D. Andrica and E. J. Ionascu, On the number of polynomials with coefficients in [n], An. St. Univ. Ovidius Constanta, 2013, to appear.

Table of n, a(n) for n=1..70.

Cf. A000005, A006318, A238097, A238098.

Sequence in context: A179543 A077471 A273324 * A064572 A032399 A276496

Adjacent sequences: A238093 A238094 A238095 * A238097 A238098 A238099

nonn

N. J. A. Sloane, Feb 22 2014

approved