A300418 Number of semiprime Fermat pseudoprimes to base 2 (A214305) less than 10^n.

0, 0, 1, 11, 34, 107, 312, 882, 2457, 6504, 17206, 46073, 123868, 334567, 915443, 2520503, 7002043, 19604493, 55264235

Offset

1,4

Links

Table of n, a(n) for n=1..19.

Jan Feitsma, The pseudoprimes below 2^64 - statistics.

William F. Galway, The Density of Pseudoprimes with Two Prime Factors.

Aran Nayebi, On the distribution of Carmichael numbers, arXiv preprint arXiv:0906.3533 [math.NT], 2009-2013. But beware of errors!

Crossrefs

Cf. A055550, A214305.

Sequence in context: A063162 A211014 A103661 * A041539 A233933 A041232

Adjacent sequences: A300415 A300416 A300417 * A300419 A300420 A300421

Keyword

nonn,more

Author

Amiram Eldar, Mar 05 2018

Extensions

Corrected and extended by Daniel Suteu, Dec 10 2019

Status

approved