A064457 a(1) = 3; for n > 1, choose a(n) to be the smallest number such that a(n) > a(n-1) and (a(n)*a(n-1)+1) mod (a(n)+a(n-1)+1) = 0.

3, 7, 47, 157, 293, 1807, 8697, 9447, 15147, 31497, 74847, 159111, 1031187, 1100457, 1740087, 3589707, 8498937, 10312173, 15086925, 51874335, 54072205, 746239895, 1433920655, 11288282053

Offset

1,1

Comments

Starting with a(1) = 0, 1 or 2 there are no solutions.

Links

Table of n, a(n) for n=1..24.

Example

a(3) = 47 because 7*47 + 1 = 330 and 7+47+1 = 55 and 55*6 = 330

Crossrefs

Sequence in context: A007670 A263806 A074714 * A318087 A005650 A020754

Adjacent sequences: A064454 A064455 A064456 * A064458 A064459 A064460

Keyword

nonn,more

Author

Jonathan Ayres (jonathan.ayres(AT)btinternet.com), Oct 15 2001

Extensions

More terms from Vladeta Jovovic, Oct 18 2001

a(24) from Sean A. Irvine, Jul 11 2023

Status

approved