A242770 Composite numbers of the form A242490(n) - 1.

4189, 12193, 641941, 8778073, 26822599, 11488195489

Offset: 1

Author

Vladimir Shevelev and Peter J. C. Moses, May 22 2014

Keywords

• nonn
• more

Comments

a(7) (if it exists) = A242490(k) - 1, k >= 5 * 10^7. - Hiroaki Yamanouchi, Sep 22 2014

Examples

			a(1) = A242490(16) - 1 = 4189 = 59 * 71;
a(2) = A242490(21) - 1 = 12193 = 89 * 137;
a(3) = A242490(125) - 1 = 641941 = 727 * 883;
a(4) = A242490(417) - 1 = 8778073 = 2927 * 2999;
a(5) = A242490(675) - 1 = 26822599 = 5081 * 5279;
a(6) = A242490(10171) - 1 = 11488195489 = 107183 * 107183.
		

Crossrefs

Cf. A242489, A242490, A242716.

Extensions

a(6) from Hiroaki Yamanouchi, Sep 22 2014