1,2

A Gaussian integer z = x+iy is in the first quadrant if x > 0, y >= 0. Just one of the 4 associates z, -z, i*z, -i*z is in the first quadrant.

The sequence is fully additive.

Table of n, a(n) for n=1..99.

Michael Somos, PARI program for finding prime decomposition of Gaussian integers

Index entries for Gaussian integers and primes

5 factors into the product of the primes 1+2*i, 1-2*i, but the first-quadrant associate of 1-2*i is i*(1-2*i) = 2+i, so r+i*s = 1+2*i + 2+i = 3+3*i. Therefore a(5) = 3.

Cf. A078458, A078908, A078910, A078911, A080088, A080089.

Sequence in context: A145382 A192423 A265584 * A067458 A088330 A324471

Adjacent sequences: A078906 A078907 A078908 * A078910 A078911 A078912

nonn,easy

N. J. A. Sloane, Jan 11 2003

More terms and further information from Vladeta Jovovic, Jan 27 2003

approved