A029846 a(n) = a(n-1)*b(n-2)+2, b() given by A029758.

1, 3, 5, 7, 23, 347, 109307, 11878938227, 141106591489900388627, 19911070158545297149320104511797515190627, 396450714858513044552818188364610837019759458190194070051140109393414330800390627

Offset: 0

Author

Don Knuth

Keywords

• easy
• nonn

References

• D. E. Knuth, Art of Computer Programming, Vol. 3, Sect. 6.2.3 (7) and (8).

Links

• Alois P. Heinz, Table of n, a(n) for n = 0..13

Programs

PARI

a(n)=if(n<3,max(0,1+2*n),2+a(n-1)*(a(n-1)-2)*(a(n-2)-2)/a(n-2)) /* Michael Somos, Feb 07 2004  */

Extensions

More terms from N. J. A. Sloane