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A112441 Pseudoprimes (base-2) equal to product of 4 primes not necessarily distinct. 1
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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified April 20 01:20 EDT 2021. Contains 343117 sequences. (Running on oeis4.)