cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A112445 Pseudoprimes (base 2) equal to the product of 7 primes not necessarily distinct.

Original entry on oeis.org

370851481, 1310486905, 1452092005, 1553860945, 2719940041, 3328293745, 3860623585, 5394826801, 5612626041, 5659475185, 6295936465, 8857509661, 9234602385, 10780911505, 10975165201, 11718888181, 12254138065, 12416553721, 12452890681, 13577445505, 14795826661
Offset: 1

Views

Author

Shyam Sunder Gupta, Dec 11 2005

Keywords

Examples

			a(1) = 370851481 = 7*11*13*17*19*31*37.
		

Crossrefs

Intersection of A046308 and A001567.

Programs

  • Mathematica
    s={}; Do[If[PrimeOmega[n] == 7 && PowerMod[2, n - 1, n] == 1, AppendTo[s, n]], {n, 1, 2*10^9}]; s (* Amiram Eldar, Nov 10 2019 *)

Extensions

More terms from Amiram Eldar, Nov 10 2019