A112441 Pseudoprimes (base-2) equal to product of 4 primes not necessarily distinct.

11305, 18705, 23001, 39865, 41041, 55245, 62745, 63973, 72885, 75361, 101101, 107185, 126217, 129921, 157641, 172081, 188461, 212421, 215265, 266305, 272251, 278545, 332949, 340561, 367081, 401401, 449065, 451905, 464185, 493885, 552721, 622909, 656601, 658801

Offset

1,1

Links

Amiram Eldar, Table of n, a(n) for n = 1..10000

Example

a(1) = 11305 = 5*7*17*19.

Mathematica

Select[Range[700000], PrimeOmega[#] == 4 && PowerMod[2, # - 1, #] == 1 &] (* Amiram Eldar, Nov 10 2019 *)

Crossrefs

Intersection of A014613 and A001567.

Sequence in context: A110375 A252859 A177216 * A104017 A317400 A284814

Adjacent sequences: A112438 A112439 A112440 * A112442 A112443 A112444

Keyword

easy,nonn

Author

Shyam Sunder Gupta, Dec 11 2005

Extensions

More terms from Amiram Eldar, Nov 10 2019

Status

approved