A275650 Number of positive integers k less than 10^n such that k is a sum of two squares and k/2 is an even power.

4, 28, 214, 1803, 15830, 142844, 1313047, 12220699, 114790260, 1085885280, 10330026070, 98719755796, 947012920362, 9113815047794, 87950106960771, 850754904051968

Offset: 1

Author

Felix Fröhlich, Aug 04 2016

Keywords

• nonn
• more

Comments

This sequence gives the values of the counting function V(x), whose values are given in table 3 on page 359 of Shiu, 1986.

Links

• P. Shiu, Counting sums of two squares: the Meissel-Lehmer method, Mathematics of Computation, 47 (1986), 351-360.

Crossrefs

Cf. A164775: W(x), A275649: U(x).

Extensions

a(12) corrected and a(13)-a(16) added by Hiroaki Yamanouchi, Dec 25 2016